diff --git a/.github/workflows/Docstrings.yml b/.github/workflows/Docstrings.yml
new file mode 100644
index 000000000000..c3ae6a2f5780
--- /dev/null
+++ b/.github/workflows/Docstrings.yml
@@ -0,0 +1,29 @@
+name: docstring test
+
+on:
+  push:
+    branches:
+      - master
+      - 'release-*'
+  pull_request:
+  workflow_dispatch:
+
+concurrency:
+  # group by workflow and ref; the last slightly strange component ensures that for pull
+  # requests, we limit to 1 concurrent job, but for the master branch we don't
+  group: ${{ github.workflow }}-${{ github.ref }}-${{ github.ref != 'refs/heads/master' || github.run_number }}
+  # Cancel intermediate builds, but only if it is a pull request build.
+  cancel-in-progress: ${{ startsWith(github.ref, 'refs/pull/') }}
+
+jobs:
+  check-docstrings:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v4
+    - uses: julia-actions/setup-julia@v2
+    - uses: julia-actions/cache@v2
+    - name: Build package
+      uses: julia-actions/julia-buildpkg@v1
+    - name: 'Check issues in docstrings'
+      run: |
+        julia --project=. -e 'using Oscar; include("etc/check_docstrings.jl")'
diff --git a/LICENSE.md b/LICENSE.md
index d5ab55d1895a..2faf769ff70e 100644
--- a/LICENSE.md
+++ b/LICENSE.md
@@ -1,6 +1,11 @@
 The Oscar.jl package is licensed under the GNU Public License, Version 3.0+:
 
-> Copyright (c) 2019 The OSCAR Development Team.
+> Copyright (c) 2019-2024 The OSCAR Development Team
+>
+> See <https://www.oscar-system.org/contributors/> for a list of OSCAR
+> Development Team members. Note that this list may occasionally be slightly
+> outdated. Additional contributors may be found in the `git log` of the main
+> OSCAR repository and other related repositories.
 > This program is free software: you can redistribute it and/or modify
 > it under the terms of the GNU General Public License as published by
 > the Free Software Foundation, either version 3 of the License, or
diff --git a/Project.toml b/Project.toml
index a8f6d8da0485..ff89d27f55f9 100644
--- a/Project.toml
+++ b/Project.toml
@@ -1,7 +1,7 @@
 name = "Oscar"
 uuid = "f1435218-dba5-11e9-1e4d-f1a5fab5fc13"
 authors = ["The OSCAR Team <oscar@oscar-system.org>"]
-version = "1.2.0"
+version = "1.2.1"
 
 [deps]
 AbstractAlgebra = "c3fe647b-3220-5bb0-a1ea-a7954cac585d"
diff --git a/README.md b/README.md
index 5dba2c6a242c..912401b4c4c6 100644
--- a/README.md
+++ b/README.md
@@ -37,7 +37,8 @@ julia> using Oscar
  / _ \ / ___| / ___|  / \  |  _ \   |  Combining ANTIC, GAP, Polymake, Singular
 | | | |\___ \| |     / _ \ | |_) |  |  Type "?Oscar" for more information
 | |_| | ___) | |___ / ___ \|  _ <   |  Manual: https://docs.oscar-system.org
- \___/ |____/ \____/_/   \_\_| \_\  |  Version 1.2.0
+ \___/ |____/ \____/_/   \_\_| \_\  |  Version 1.2.1
+
 julia> k, a = quadratic_field(-5)
 (Imaginary quadratic field defined by x^2 + 5, sqrt(-5))
 
@@ -113,7 +114,7 @@ pm::Array<topaz::HomologyGroup<pm::Integer> >
 If you have used OSCAR in the preparation of a paper please cite it as described below:
 
     [OSCAR]
-        OSCAR -- Open Source Computer Algebra Research system, Version 1.2.0,
+        OSCAR -- Open Source Computer Algebra Research system, Version 1.2.1,
         The OSCAR Team, 2024. (https://www.oscar-system.org)
     [OSCAR-book]
         Wolfram Decker, Christian Eder, Claus Fieker, Max Horn, Michael Joswig, eds.
@@ -126,7 +127,7 @@ If you are using BibTeX, you can use the following BibTeX entries:
       key          = {OSCAR},
       organization = {The OSCAR Team},
       title        = {OSCAR -- Open Source Computer Algebra Research system,
-                      Version 1.2.0},
+                      Version 1.2.1},
       year         = {2024},
       url          = {https://www.oscar-system.org},
       }
diff --git a/docs/Project.toml b/docs/Project.toml
index 07d7ae149a80..6dad0075f817 100644
--- a/docs/Project.toml
+++ b/docs/Project.toml
@@ -1,7 +1,9 @@
 [deps]
 Documenter = "e30172f5-a6a5-5a46-863b-614d45cd2de4"
 DocumenterCitations = "daee34ce-89f3-4625-b898-19384cb65244"
+JSON = "682c06a0-de6a-54ab-a142-c8b1cf79cde6"
 
 [compat]
 Documenter = "1.1"
 DocumenterCitations = "~1.3.4"
+JSON = "0.21.4"
diff --git a/docs/make_work.jl b/docs/make_work.jl
index b3a0aec16741..91efab27a67c 100644
--- a/docs/make_work.jl
+++ b/docs/make_work.jl
@@ -4,7 +4,7 @@
 #
 module BuildDoc
 
-using Documenter, DocumenterCitations
+using Documenter, DocumenterCitations, JSON
 
 include("documenter_helpers.jl")
 include("citation_style.jl")
@@ -210,6 +210,56 @@ function doit(
     dstbase = normpath(Oscar.oscardir, "docs", "src", string(nameof(pkg)))
     rm(dstbase; recursive=true, force=true)
   end
+  
+  # postprocessing, for the search index
+  docspath = normpath(joinpath(Oscar.oscardir, "docs"))
+  @info "Patching search index."
+  # extract valid json from search_index.js
+  run(pipeline(`sed -n '2p;3q' $(joinpath(docspath, "build", "search_index.js"))`, stdout=(joinpath(docspath, "build", "search_index.json")))) # imperfect file, but JSON parses it
+  
+  # extract paths from doc.main
+  filelist=String[]
+  docmain = include(joinpath(docspath, "doc.main"))
+  while !isempty(docmain)
+    n = pop!(docmain)
+    if n isa Pair
+      push!(docmain, last(n))
+    elseif n isa String
+      push!(filelist, n)
+    elseif n isa Array{String}
+      append!(filelist,n)
+    elseif n isa Array
+      append!(docmain,n)
+    else
+      error("err: $(typeof(n))")
+    end
+  end
+  suffix = local_build ? ".html" : "/"
+  filelist = replace.(filelist, r"\.md$"=>suffix)
+
+  # read these files
+  iosearchindex = open(joinpath(docspath, "build", "search_index.json"), "r")
+  searchindex = JSON.parse(iosearchindex)
+  close(iosearchindex)
+  
+  newsearchindex = []
+  
+  for item in searchindex
+    if split(item["location"], "#")[1] in filelist
+      push!(newsearchindex, item)
+    end
+  end
+  
+  
+  # combine this to valid javascript again, and overwrite input
+  ionewsearchindex = open(joinpath(docspath, "build", "search_index.js"), "w")
+  write(ionewsearchindex, """var documenterSearchIndex = {"docs":\n""")
+  JSON.print(ionewsearchindex, newsearchindex)
+  write(ionewsearchindex, "\n}")
+  close(ionewsearchindex)
+
+  # clean up
+  rm(joinpath(docspath, "build", "search_index.json"))
 end
 
 end # module BuildDoc
diff --git a/docs/oscar_references.bib b/docs/oscar_references.bib
index c6e93053f394..f4d98cea61df 100644
--- a/docs/oscar_references.bib
+++ b/docs/oscar_references.bib
@@ -34,7 +34,7 @@ @Article{AG10
   number        = {1},
   pages         = {3--24},
   year          = {2010},
-  eprint        = {0810.1148}
+  doi           = {10.1070/SM2010v201n01ABEH004063}
 }
 
 @InProceedings{AGK96,
@@ -155,6 +155,7 @@ @InProceedings{BDLP19
   booktitle     = {MEGA 2019 - International Conference on Effective Methods in Algebraic Geometry},
   address       = {Madrid, Spain},
   year          = {2019},
+  doi           = {10.1016/j.jsc.2020.07.007},
   archiveprefix = {HAL},
   eprint        = {hal-02912148}
 }
@@ -193,13 +194,17 @@ @InProceedings{BES-E-D21
   location      = {Virtual Event, Russian Federation}
 }
 
-@Misc{BES19,
+@Article{BES23,
   author        = {Backman, Spencer and Eur, Christopher and Simpson, Connor},
   title         = {Simplicial generation of Chow rings of matroids},
-  year          = {2019},
-  eprint        = {1905.07114},
-  archiveprefix = {arXiv},
-  primaryclass  = {math.CO}
+  journal       = {JEMS},
+  fjournal      = {Journal of the European Mathematical Society},
+  volume        = {26},
+  number        = {11},
+  pages         = {4491--4535},
+  year          = {2023},
+  month         = jun,
+  doi           = {10.4171/jems/1350}
 }
 
 @Book{BGV03,
@@ -236,13 +241,15 @@ @Article{BH23
   doi           = {10.1017/fms.2023.50}
 }
 
-@Misc{BHMPW20,
+@Article{BHMPW22,
   author        = {Braden, Tom and Huh, June and Matherne, Jacob P. and Proudfoot, Nicholas and Wang, Botong},
   title         = {A semi-small decomposition of the Chow ring of a matroid},
-  year          = {2020},
-  eprint        = {2002.03341},
-  archiveprefix = {arXiv},
-  primaryclass  = {math.AG}
+  journal       = {Advances in Mathematics},
+  volume        = {409},
+  pages         = {108646},
+  year          = {2022},
+  month         = nov,
+  doi           = {10.1016/j.aim.2022.108646}
 }
 
 @Book{BHPV-D-V04,
@@ -254,6 +261,7 @@ @Book{BHPV-D-V04
   publisher     = {Berlin: Springer},
   edition       = {2nd enlarged ed.},
   year          = {2004},
+  doi           = {10.1007/978-3-642-57739-0},
   fseries       = {Ergebnisse der Mathematik und ihrer Grenzgebiete. 3. Folge},
   language      = {English},
   zbmath        = {2008523}
@@ -364,7 +372,8 @@ @Book{Ben93
   volume        = {190},
   address       = {Cambridge},
   publisher     = {Cambridge University Press},
-  year          = {1993}
+  year          = {1993},
+  doi           = {10.1017/CBO9780511565809}
 }
 
 @MastersThesis{Bhm99,
@@ -409,14 +418,15 @@ @Article{Bis96
   doi           = {10.1112/S0025579300011773}
 }
 
-@Book{Bur55,
+@Book{Bur11,
   author        = {Burnside, W.},
   title         = {Theory of groups of finite order},
   mrnumber      = {69818},
   note          = {2d ed},
   publisher     = {Dover Publications, Inc., New York},
   pages         = {xxiv+512},
-  year          = {1955}
+  year          = {1911},
+  doi           = {10.1017/CBO9781139237253}
 }
 
 @Book{C-MLS20,
@@ -633,6 +643,7 @@ @InCollection{DE02
   publisher     = {Berlin: Springer},
   pages         = {215--249},
   year          = {2002},
+  doi           = {10.1007/978-3-662-04851-1_9},
   language      = {English},
   zbmath        = {1693054}
 }
@@ -742,7 +753,8 @@ @Article{DK17
   fjournal      = {Journal of Algebra},
   volume        = {472},
   pages         = {546--572},
-  year          = {2017}
+  year          = {2017},
+  doi           = {10.1016/j.jalgebra.2016.10.042}
 }
 
 @Book{DL06,
@@ -803,6 +815,7 @@ @Book{DSS09
   volume        = {39},
   publisher     = {Basel: Birkhäuser},
   year          = {2009},
+  doi           = {10.1007/978-3-7643-8905-5},
   fseries       = {Oberwolfach Seminars},
   language      = {English},
   zbmath        = {5303649}
@@ -1001,6 +1014,7 @@ @InProceedings{FLINT
   publisher     = {Springer-Verlag},
   pages         = {88--91},
   year          = {2010},
+  doi           = {10.1007/978-3-642-15582-6_18},
   location      = {Kobe, Japan},
   numpages      = {4}
 }
@@ -1050,7 +1064,8 @@ @Book{Ful97
   note          = {With applications to representation theory and geometry},
   publisher     = {Cambridge University Press, Cambridge},
   pages         = {x+260},
-  year          = {1997}
+  year          = {1997},
+  doi           = {10.1017/CBO9780511626241}
 }
 
 @Book{Ful98,
@@ -1087,7 +1102,8 @@ @InProceedings{GHJ16
   address       = {Cham},
   publisher     = {Springer International Publishing},
   pages         = {403--410},
-  year          = {2016}
+  year          = {2016},
+  doi           = {10.1007/978-3-319-42432-3_50}
 }
 
 @Article{GIR96,
@@ -1133,7 +1149,8 @@ @InProceedings{GK14
   booktitle     = {Proceedings of the fifteenth ACM conference on Economics and computation},
   publisher     = {Association for Computing Machinery, New York},
   pages         = {259--276},
-  year          = {2014}
+  year          = {2014},
+  doi           = {10.1145/2600057.2602883}
 }
 
 @Book{GLS07,
@@ -1418,7 +1435,8 @@ @Article{JKS22
   number        = {4},
   publisher     = {SIAM},
   pages         = {711--739},
-  year          = {2022}
+  year          = {2022},
+  doi           = {10.1137/21M1441286}
 }
 
 @Article{JLLT22,
@@ -1522,7 +1540,8 @@ @Book{Jos21
   volume        = {219},
   address       = {Providence, RI},
   publisher     = {American Mathematical Society},
-  year          = {2021}
+  year          = {2021},
+  doi           = {10.1090/gsm/219}
 }
 
 @Article{Jow11,
@@ -1616,7 +1635,8 @@ @InCollection{KS99
   volume        = {173},
   publisher     = {Birkhäuser, Basel},
   pages         = {267--285},
-  year          = {1999}
+  year          = {1999},
+  doi           = {10.1007/978-3-0348-8716-8_17}
 }
 
 @Article{Kah10,
@@ -1692,6 +1712,7 @@ @Book{Kol13
   note          = {With a collaboration of Sándor Kovács},
   publisher     = {Cambridge University Press},
   year          = {2013},
+  doi           = {10.1017/CBO9781139547895},
   location      = {Cambridge}
 }
 
@@ -1774,7 +1795,8 @@ @Book{Loo84
   volume        = {77},
   publisher     = {Cambridge University Press, Cambridge},
   pages         = {xi+200},
-  year          = {1984}
+  year          = {1984},
+  doi           = {10.1017/CBO9780511662720}
 }
 
 @Misc{MNP24,
@@ -1834,7 +1856,8 @@ @Book{MS15
   volume        = {161},
   publisher     = {Providence, RI: American Mathematical Society (AMS)},
   pages         = {xii + 363},
-  year          = {2015}
+  year          = {2015},
+  doi           = {10.1090/gsm/161}
 }
 
 @Book{MS21,
@@ -2012,7 +2035,8 @@ @Article{Pos09
   number        = {6},
   publisher     = {OUP},
   pages         = {1026--1106},
-  year          = {2009}
+  year          = {2009},
+  doi           = {10.1093/imrn/rnn153}
 }
 
 @Article{Pos18,
@@ -2048,13 +2072,14 @@ @Article{RR10
   doi           = {10.1063/1.3501135}
 }
 
-@Article{RSS03,
+@InBook{RSS03,
   author        = {Rote, Günter and Santos, Francisco and Streinu, Ileana},
   title         = {Expansive motions and the polytope of pointed pseudo-triangulations},
-  journal       = {Discrete and Computational Geometry: The Goodman-Pollack Festschrift},
+  booktitle     = {Discrete and Computational Geometry},
   publisher     = {Springer},
   pages         = {699--736},
-  year          = {2003}
+  year          = {2003},
+  doi           = {10.1007/978-3-642-55566-4_33}
 }
 
 @Article{Rin13,
@@ -2078,6 +2103,7 @@ @Book{SS03
   volume        = {24},
   publisher     = {Oxford University Press},
   year          = {2003},
+  doi           = {10.1093/oso/9780198509424.001.0001},
   fseries       = {Oxford Lecture Series in Mathematics and its Applications}
 }
 
@@ -2191,7 +2217,8 @@ @Article{Sta79
   volume        = {1},
   number        = {3},
   pages         = {475--511},
-  year          = {1979}
+  year          = {1979},
+  doi           = {10.1090/S0273-0979-1979-14597-X}
 }
 
 @Misc{Stacks,
diff --git a/docs/src/Groups/tom.md b/docs/src/Groups/tom.md
index fb04e7274c40..05f64e78bfe2 100644
--- a/docs/src/Groups/tom.md
+++ b/docs/src/Groups/tom.md
@@ -6,7 +6,7 @@ DocTestSetup = Oscar.doctestsetup()
 # Tables of Marks
 
 The concept of a *Table of Marks* was introduced by W. Burnside in his book
-Theory  of Groups of Finite Order [Bur55](@cite).
+Theory  of Groups of Finite Order [Bur11](@cite).
 Therefore a table of marks is sometimes called a *Burnside matrix*.
 The table of marks of a finite group ``G`` is a matrix whose rows and columns
 are labelled by the conjugacy classes of subgroups of ``G`` and where for
diff --git a/etc/check_docstrings.jl b/etc/check_docstrings.jl
new file mode 100644
index 000000000000..72caa4d49495
--- /dev/null
+++ b/etc/check_docstrings.jl
@@ -0,0 +1,107 @@
+# this can be run from the command line with:
+# > julia --project=. -e 'using Oscar; include("etc/check_docstrings.jl")'
+#
+# it is also possible to test more packages at once (as long as Main.X exists)
+# > julia --project=. -e 'using Oscar; include("etc/check_docstrings.jl")' Nemo Singular Hecke Polymake GAP Oscar
+#
+# note: the @main function requires julia 1.11 or newer
+
+
+using Markdown
+
+admonition_types = string.((:note, :info, :tip, :danger, :warning, :compat, :todo, :details))
+
+# this might not catch all broken jldoctests but seems to work for now
+function has_broken_doctest(md::Markdown.MD)
+  todo = copy(md.content)
+  while !isempty(todo)
+    elem = popfirst!(todo)
+    # nested
+    if elem isa Markdown.MD
+      append!(todo, elem.content)
+    else
+      # proper docstrings are in a Markdown.Code block
+      if elem isa Markdown.Paragraph
+        for block in elem.content
+          # unterminated jldoctests seem to end up inside some string in a Paragraph block
+          if contains(string(block),"```jldoctest")
+            return "Unterminated jldoctest: $(string(block))"
+          end
+        end
+      elseif elem isa Markdown.Admonition
+        if !(elem.category in admonition_types)
+          return "Unknown admonition category: $(string(elem.category))"
+        end
+      end
+    end
+  end
+  return nothing
+end
+
+function find_docstr_src(docs)
+  locs = []
+  res = docs.meta[:results]
+  for i in 1:length(docs.content)
+    msg = has_broken_doctest(docs.content[i])
+    if msg !== nothing
+      file = res[i].data[:path]
+      line = res[i].data[:linenumber]
+      mod = res[i].data[:module]
+      push!(locs, (mod, file, line, msg))
+    end
+  end
+  return locs
+end
+
+function get_broken_docstrings(m::Module)
+  allpairs = collect(zip(Iterators.repeated(m), names(m; all=true, imported=false)));
+  broken = []
+  locs = []
+  done = [m]
+
+  while !isempty(allpairs)
+    (src, name) = popfirst!(allpairs)
+    memberobj = try
+      getfield(src,name)
+    catch
+      nothing
+    end
+    if memberobj isa Module
+      if !(memberobj in done)
+        push!(done, memberobj)
+        # we only want to consider one pkg
+        # but note that we still seem to pick up some reexported names
+        # even though imported=false and the check below
+        if (pkgdir(memberobj) == pkgdir(m))
+          newnames = names(memberobj; all=true, imported=false)
+          filter!(x->!((memberobj, x) in allpairs || x in done), newnames)
+          append!(allpairs, collect(zip(Iterators.repeated(memberobj), newnames)))
+        end
+      end
+    elseif !isnothing(memberobj)
+      docs = Base.Docs.doc(memberobj)
+      if docs isa Markdown.MD
+        if has_broken_doctest(docs) !== nothing && !(memberobj in broken)
+          loc = find_docstr_src(docs)
+          push!(broken, memberobj)
+          # we could filter out docs from other packages via startswith(x, pkgdir(m))
+          append!(locs, loc)
+        end
+      end
+    end
+  end
+  return locs
+end
+
+function (@main)(args)
+  modnames = length(args) > 0 ? args : ["Oscar"]
+  mod = getfield.(Ref(Main), Symbol.(modnames))
+  locs = reduce(vcat, get_broken_docstrings.(mod))
+  isempty(locs) && exit(0)
+  for (mod, file, line, msg) in locs
+    dir = joinpath(pkgdir(mod),"") # add trailing /
+    relfile = replace(file, dir => "")
+    println("::error file=$relfile,line=$line,title=$(string(mod))::$msg")
+  end
+  exit(-1)
+end
diff --git a/experimental/BasisLieHighestWeight/src/UserFunctions.jl b/experimental/BasisLieHighestWeight/src/UserFunctions.jl
index 8a69177f94dc..d9bb839a79ae 100644
--- a/experimental/BasisLieHighestWeight/src/UserFunctions.jl
+++ b/experimental/BasisLieHighestWeight/src/UserFunctions.jl
@@ -406,7 +406,7 @@ with highest weight `highest_weight` for a simple Lie algebra $L$ of type `type`
 Furthermore, for each degree, return the monomials that are not contained in the Minkowski sum
 of the bases of the lower degrees.
 
-!!! warn
+!!! warning
     Currently, this function expects $-w_0(\lambda)$ instead of $\lambda$ as the `highest_weight` input.
     This might change in a minor release.
     
@@ -515,7 +515,7 @@ with highest weight `highest_weight` for a simple Lie algebra $L$ of type `type`
 Furthermore, for each degree, return the monomials that are not contained in the Minkowski sum
 of the bases of the lower degrees.
 
-!!! warn
+!!! warning
     Currently, this function expects $-w_0(\lambda)$ instead of $\lambda$ as the `highest_weight` input.
     This might change in a minor release.
 
diff --git a/experimental/SetPartitions/src/SetPartition.jl b/experimental/SetPartitions/src/SetPartition.jl
index dab1433dc8d7..3bb6a44ec548 100644
--- a/experimental/SetPartitions/src/SetPartition.jl
+++ b/experimental/SetPartitions/src/SetPartition.jl
@@ -84,6 +84,7 @@ julia> lower_points(set_partition([2, 4], [4, 99]))
 2-element Vector{Int64}:
  2
  3
+```
 """
 function lower_points(p::SetPartition)
     return p.lower_points
diff --git a/gap/OscarInterface/PackageInfo.g b/gap/OscarInterface/PackageInfo.g
index 8a7bbc2c1a8c..70ccf1e30b3d 100644
--- a/gap/OscarInterface/PackageInfo.g
+++ b/gap/OscarInterface/PackageInfo.g
@@ -10,8 +10,8 @@ SetPackageInfo( rec(
 
 PackageName := "OscarInterface",
 Subtitle := "GAP interface to OSCAR",
-Version := "1.2.0",
-Date := "30/10/2024", # dd/mm/yyyy format
+Version := "1.2.1",
+Date := "20/11/2024", # dd/mm/yyyy format
 License := "GPL-2.0-or-later",
 
 Persons := [
diff --git a/src/AlgebraicGeometry/Schemes/AffineSchemes/Objects/Methods.jl b/src/AlgebraicGeometry/Schemes/AffineSchemes/Objects/Methods.jl
index 724c56802dcf..6319cd4d9887 100644
--- a/src/AlgebraicGeometry/Schemes/AffineSchemes/Objects/Methods.jl
+++ b/src/AlgebraicGeometry/Schemes/AffineSchemes/Objects/Methods.jl
@@ -473,3 +473,8 @@ function _change_base_ring(phi::Any,
   @assert _has_coefficient_map(res_map)
   return L_red, res_map
 end
+
+function Base.hash(X::Scheme, u::UInt)
+  return u
+end
+
diff --git a/src/AlgebraicGeometry/Schemes/Divisors/AlgebraicCycles.jl b/src/AlgebraicGeometry/Schemes/Divisors/AlgebraicCycles.jl
index 82806d80c191..ea7b74e85290 100644
--- a/src/AlgebraicGeometry/Schemes/Divisors/AlgebraicCycles.jl
+++ b/src/AlgebraicGeometry/Schemes/Divisors/AlgebraicCycles.jl
@@ -534,3 +534,7 @@ function integral(W::AbsAlgebraicCycle; check::Bool=true)
   return result
 end
 
+function Base.hash(X::AbsAlgebraicCycle, u::UInt)
+  return u
+end
+
diff --git a/src/AlgebraicGeometry/Schemes/Divisors/CartierDivisor.jl b/src/AlgebraicGeometry/Schemes/Divisors/CartierDivisor.jl
index 34c5e1255791..36f7e74ae448 100644
--- a/src/AlgebraicGeometry/Schemes/Divisors/CartierDivisor.jl
+++ b/src/AlgebraicGeometry/Schemes/Divisors/CartierDivisor.jl
@@ -530,3 +530,12 @@ function _show_semi_compact(io::IO, C::CartierDivisor, cov::Covering, n::String)
     print(io, Dedent())
   end
 end
+
+function Base.hash(X::CartierDivisor, u::UInt)
+  return u
+end
+
+function Base.hash(X::EffectiveCartierDivisor, u::UInt)
+  return u
+end
+
diff --git a/src/AlgebraicGeometry/Schemes/Gluing/Methods.jl b/src/AlgebraicGeometry/Schemes/Gluing/Methods.jl
index 7024fc902e00..70b9e81c97e4 100644
--- a/src/AlgebraicGeometry/Schemes/Gluing/Methods.jl
+++ b/src/AlgebraicGeometry/Schemes/Gluing/Methods.jl
@@ -236,3 +236,7 @@ function base_change(phi::Any, G::AbsGluing;
   return LazyGluing(domain(patch_change1), domain(patch_change2), gd)
 end
 
+function Base.hash(X::AbsGluing, u::UInt)
+  return u
+end
+
diff --git a/src/AlgebraicGeometry/Schemes/ProjectiveSchemes/Objects/Methods.jl b/src/AlgebraicGeometry/Schemes/ProjectiveSchemes/Objects/Methods.jl
index 20e2c51d5841..cb9bbb3b3543 100644
--- a/src/AlgebraicGeometry/Schemes/ProjectiveSchemes/Objects/Methods.jl
+++ b/src/AlgebraicGeometry/Schemes/ProjectiveSchemes/Objects/Methods.jl
@@ -433,5 +433,8 @@ function Base.union(comp::Vector{<:AbsProjectiveScheme})
   return result
 end
 
+function Base.hash(X::AbsProjectiveScheme, u::UInt)
+  return u
+end
 
 
diff --git a/src/AlgebraicGeometry/Schemes/Sheaves/CoherentSheaves.jl b/src/AlgebraicGeometry/Schemes/Sheaves/CoherentSheaves.jl
index 2bf4fb32bdc8..cdd99771ec45 100644
--- a/src/AlgebraicGeometry/Schemes/Sheaves/CoherentSheaves.jl
+++ b/src/AlgebraicGeometry/Schemes/Sheaves/CoherentSheaves.jl
@@ -1116,4 +1116,7 @@ function projectivization(E::AbsCoherentSheaf;
   return CoveredProjectiveScheme(X, C, on_patches, projective_gluings, check=false)
 end
 
+function Base.hash(X::AbsCoherentSheaf, u::UInt)
+  return u
+end
 
diff --git a/src/Combinatorics/EnumerativeCombinatorics/tableaux.jl b/src/Combinatorics/EnumerativeCombinatorics/tableaux.jl
index 522c13f0fdbb..61aa41ad3241 100644
--- a/src/Combinatorics/EnumerativeCombinatorics/tableaux.jl
+++ b/src/Combinatorics/EnumerativeCombinatorics/tableaux.jl
@@ -48,7 +48,7 @@ young_tableau
 
 function young_tableau(::Type{T}, v::Vector{Vector{TT}}; check::Bool = true) where {T <: IntegerUnion, TT <: IntegerUnion}
   if check
-    @req _defines_partition(map(length, v)) "The input does not define a Young tableau"
+    @req _defines_partition(map(length, v)) "The input does not define a Young tableau: lengths of rows must be weakly decreasing"
   end
   return YoungTableau{T}(v)
 end
@@ -222,20 +222,24 @@ Return the shape of the tableau `tab`, i.e. the partition given by the lengths
 of the rows of the tableau.
 """
 function shape(tab::YoungTableau{T}) where T
-  return partition(T[ length(tab[i]) for i = 1:length(tab) ], check = false)
+  # Line below DOES NOT CHECK that the lengths of the rows are weakly decreasing
+  return partition(T[ length(tab[i]) for i = 1:length(tab) ]; check = false)
 end
 
 @doc raw"""
     weight(tab::YoungTableau)
 
-Return the weight of the tableau `tab` as an array whose `i`-th element gives
-the number of times the integer `i` appears in the tableau.
+Return the weight sequence of the tableau `tab` as an array whose `i`-th element
+gives the number of times the integer `i` appears in the tableau.
 """
 function weight(tab::YoungTableau)
+  @req  is_semistandard(tab)  "Tableau must be (semi-)standard"
+  
   if isempty(tab)
     return Int[]
   end
 
+  # Computation of max must be changed if we want to permit non-semi-standard YT
   max = 0
   for i = 1:length(tab)
     if max < tab[i][end]
diff --git a/src/Combinatorics/Matroids/ChowRings.jl b/src/Combinatorics/Matroids/ChowRings.jl
index 6e98d0cec084..dbcefb19380c 100644
--- a/src/Combinatorics/Matroids/ChowRings.jl
+++ b/src/Combinatorics/Matroids/ChowRings.jl
@@ -3,7 +3,7 @@
 
 Return the Chow ring of a matroid, optionally also with the simplicial generators and the polynomial ring.
 
-See [AHK18](@cite) and [BES19](@cite). 
+See [AHK18](@cite) and [BES23](@cite).
 
 # Examples
 The following computes the Chow ring of the Fano matroid.
@@ -141,7 +141,7 @@ end
 @doc raw"""
     augmented_chow_ring(M::Matroid)
 
-Return an augmented Chow ring of a matroid. As described in [BHMPW20](@cite). 
+Return an augmented Chow ring of a matroid. As described in [BHMPW22](@cite).
 
 # Examples
 ```jldoctest
diff --git a/src/Combinatorics/Matroids/matroids.jl b/src/Combinatorics/Matroids/matroids.jl
index 4e028825fd1f..af2a530d4556 100644
--- a/src/Combinatorics/Matroids/matroids.jl
+++ b/src/Combinatorics/Matroids/matroids.jl
@@ -278,9 +278,9 @@ function matroid_from_hyperplanes(hyperplanes::Union{AbstractVector{T},AbstractS
 end
 
 @doc raw"""
-    matroid_from_matrix_columns(A::MatrixElem)
+    matroid_from_matrix_columns(A::MatrixElem; check::Bool=true)
 
-A matroid represented by the column vectors of a matrix `A`.
+A matroid represented by the column vectors of a matrix `A`. The value of `check` is currently ignored.
 
 See Section 1.1 of [Oxl11](@cite).
 
@@ -310,13 +310,13 @@ function matroid_from_matrix_columns(A::MatrixElem; check::Bool=true)
         end
     end
 
-    return matroid_from_bases(bases, ncols(A); check=check)
+    return matroid_from_bases(bases, ncols(A); check=false)
 end
 
 @doc raw"""
-    matroid_from_matrix_columns(A::MatrixElem)
+    matroid_from_matrix_rows(A::MatrixElem, check::Bool=true)
 
-A matroid represented by the row vectors of a matrix.
+A matroid represented by the row vectors of a matrix. The value of `check` is currently ignored.
 
 See Section 1.1 of [Oxl11](@cite).
 
diff --git a/src/Combinatorics/Matroids/properties.jl b/src/Combinatorics/Matroids/properties.jl
index 56bf952a350f..addae6cad2e0 100644
--- a/src/Combinatorics/Matroids/properties.jl
+++ b/src/Combinatorics/Matroids/properties.jl
@@ -1059,11 +1059,9 @@ julia> matroid_hex(fano_matroid())
 function matroid_hex(M::Matroid)
   rvlx = min_revlex_basis_encoding(M)
   r,n = rank(M), length(M) 
+  v = zeros(Int, 4*ceil(Int, length(rvlx)/4))
+  v[length(v)-length(rvlx)+1:end] = _revlex_basis_to_vector(rvlx)
 
-  v = _revlex_basis_to_vector(rvlx)
-  for _ in 1:(4-length(v)%4)
-    pushfirst!(v,0)
-  end
   v = reshape(v,4,:)
   v = [string(parse(Int, join(v[:, j]), base=2), base=16) for j in 1:size(v)[2]]
 
diff --git a/src/Groups/homomorphisms.jl b/src/Groups/homomorphisms.jl
index e42a1cc7d151..6b1424491325 100644
--- a/src/Groups/homomorphisms.jl
+++ b/src/Groups/homomorphisms.jl
@@ -9,7 +9,7 @@ function Base.show(io::IO, x::GAPGroupHomomorphism)
 end
 
 
-function ==(f::GAPGroupHomomorphism{S,T}, g::GAPGroupHomomorphism{S,T}) where S where T
+function ==(f::GAPGroupHomomorphism, g::GAPGroupHomomorphism)
   return GapObj(f) == GapObj(g)
 end
 
diff --git a/src/Groups/sub.jl b/src/Groups/sub.jl
index b107a3062912..95162c68fa3c 100644
--- a/src/Groups/sub.jl
+++ b/src/Groups/sub.jl
@@ -157,15 +157,7 @@ end
 
 # convert a GAP list of subgroups into a vector of Julia groups objects
 function _as_subgroups(G::T, subs::GapObj) where T <: GAPGroup
-  res = Vector{T}(undef, length(subs))
-  for i = 1:length(res)
-    res[i] = _as_subgroup_bare(G, subs[i]::GapObj)
-  end
-  return res
-end
-
-function _as_subgroups(G::PcGroup, subs::GapObj)
-  res = Vector{SubPcGroup}(undef, length(subs))
+  res = Vector{sub_type(T)}(undef, length(subs))
   for i = 1:length(res)
     res[i] = _as_subgroup_bare(G, subs[i]::GapObj)
   end
diff --git a/src/NumberTheory/NmbThy.jl b/src/NumberTheory/NmbThy.jl
index 7f8921b85823..d82d3142dab6 100644
--- a/src/NumberTheory/NmbThy.jl
+++ b/src/NumberTheory/NmbThy.jl
@@ -126,10 +126,10 @@ end
 
 norm_equation(R::AbsNumFieldOrder, k::Base.Integer; abs::Bool = false) = norm_equation(R, ZZRingElem(k), abs = abs)
 
-function norm_equation_fac_elem(R::Hecke.RelNumFieldOrder{AbsSimpleNumFieldElem,Hecke.AbsSimpleNumFieldOrderFractionalIdeal}, a::AbsNumFieldOrderElem{AbsSimpleNumField,AbsSimpleNumFieldElem})
+function norm_equation_fac_elem(R::Hecke.RelNumFieldOrder{AbsSimpleNumFieldElem,Hecke.AbsSimpleNumFieldOrderFractionalIdeal}, a::AbsSimpleNumFieldOrderElem)
 
   @assert Hecke.is_maximal(R)
-  Ka, mKa, mkK = absolute_field(Hecke.nf(R))
+  Ka, mKa, mkK = collapse_top_layer(Hecke.nf(R))
   Ra = maximal_order(Ka)
   class_group(Ra)
   k = Hecke.nf(parent(a))
@@ -144,9 +144,9 @@ function norm_equation_fac_elem(R::Hecke.RelNumFieldOrder{AbsSimpleNumFieldElem,
   q, mms = snf(q)
   mq = mq*inv(mms)
 
-  C = vcat([matrix(FlintZZ, 1, ngens(q), [valuation(mS(preimage(mq, q[i])), p) for i=1:ngens(q)]) for p = keys(lp)])
+  C = reduce(vcat, (matrix(FlintZZ, 1, ngens(q), [valuation(mS(preimage(mq, q[i])), p) for i=1:ngens(q)]) for p = keys(lp)))
   
-  A = vcat([matrix(FlintZZ, 1, ngens(q), [valuation(norm(mkK, mS(preimage(mq, g))), p) for g in gens(q)]) for p = keys(la)])
+  A = reduce(vcat, (matrix(FlintZZ, 1, ngens(q), [valuation(norm(mkK, mS(preimage(mq, g))), p) for g in gens(q)]) for p = keys(la)))
   b = matrix(FlintZZ, length(la), 1, [valuation(a, p) for p = keys(la)])
 
   so = solve_mixed(A, b, C)
@@ -168,9 +168,9 @@ function norm_equation_fac_elem(R::Hecke.RelNumFieldOrder{AbsSimpleNumFieldElem,
   return sol
 end
 
-norm_equation(R::Hecke.RelNumFieldOrder{AbsSimpleNumFieldElem,Hecke.AbsSimpleNumFieldOrderFractionalIdeal}, a::AbsNumFieldOrderElem{AbsSimpleNumField,AbsSimpleNumFieldElem}) = map(x -> R(evaluate(x)), norm_equation_fac_elem(R, a))
+norm_equation(R::Hecke.RelNumFieldOrder{AbsSimpleNumFieldElem,Hecke.AbsSimpleNumFieldOrderFractionalIdeal}, a::AbsSimpleNumFieldOrderElem) = map(x -> R(evaluate(x)), norm_equation_fac_elem(R, a))
 
-function is_irreducible(a::AbsNumFieldOrderElem{AbsSimpleNumField,AbsSimpleNumFieldElem})
+function is_irreducible(a::AbsSimpleNumFieldOrderElem)
   if iszero(a)
     return false
   end
@@ -206,11 +206,11 @@ function is_irreducible(a::AbsNumFieldOrderElem{AbsSimpleNumField,AbsSimpleNumFi
 end
 
 @doc raw"""
-    irreducibles(S::Vector{AbsNumFieldOrderIdeal{AbsSimpleNumField,AbsSimpleNumFieldElem}}) -> Vector{AbsNumFieldOrderElem}
+    irreducibles(S::Vector{AbsSimpleNumFieldOrderIdeal}) -> Vector{AbsNumFieldOrderElem}
 
 Return all irreducibles whose support is contained in $S$.
 """
-function irreducibles(S::Vector{AbsNumFieldOrderIdeal{AbsSimpleNumField,AbsSimpleNumFieldElem}})
+function irreducibles(S::Vector{AbsSimpleNumFieldOrderIdeal})
   if length(S) == 0
     return []
   end
@@ -268,11 +268,11 @@ end
 =#
 
 @doc raw"""
-    factorizations(a::AbsNumFieldOrderElem{AbsSimpleNumField,AbsSimpleNumFieldElem}) -> Vector{Fac{OrdElem}}
+    factorizations(a::AbsSimpleNumFieldOrderElem) -> Vector{Fac{OrdElem}}
 
 Return all factorizations of $a$ into irreducibles.
 """
-function factorizations(a::AbsNumFieldOrderElem{AbsSimpleNumField,AbsSimpleNumFieldElem})
+function factorizations(a::AbsSimpleNumFieldOrderElem)
   O = parent(a)
   S = collect(keys(factor(a*O)))
   if length(S) == 0
@@ -302,7 +302,7 @@ function factorizations(a::AbsNumFieldOrderElem{AbsSimpleNumField,AbsSimpleNumFi
     end
   end
   sol = solve_non_negative(A, b)
-  res = Fac{AbsNumFieldOrderElem{AbsSimpleNumField,AbsSimpleNumFieldElem}}[]
+  res = Fac{AbsSimpleNumFieldOrderElem}[]
   for j=1:nrows(sol)
     x = Dict{typeof(a), Int}()
     y = a
diff --git a/src/PolyhedralGeometry/Cone/properties.jl b/src/PolyhedralGeometry/Cone/properties.jl
index 9aaf989ef0cb..6e56e125921c 100644
--- a/src/PolyhedralGeometry/Cone/properties.jl
+++ b/src/PolyhedralGeometry/Cone/properties.jl
@@ -534,7 +534,7 @@ is_fulldimensional(C::Cone) = pm_object(C).FULL_DIM::Bool
 Return the facets of `C` in the format defined by `as`.
 
 The allowed values for `as` are
-* `Halfspace`,
+* `Halfspace` (or its subtype `LinearHalfspace`),
 * `Cone`.
 
 # Examples
diff --git a/src/PolyhedralGeometry/Polyhedron/properties.jl b/src/PolyhedralGeometry/Polyhedron/properties.jl
index a7ad3ae9656a..c400ea1bce88 100644
--- a/src/PolyhedralGeometry/Polyhedron/properties.jl
+++ b/src/PolyhedralGeometry/Polyhedron/properties.jl
@@ -491,7 +491,7 @@ end
 Return the facets of `P` in the format defined by `as`.
 
 The allowed values for `as` are
-* `Halfspace`,
+* `Halfspace` (or its subtype `AffineHalfspace`),
 * `Polyhedron`,
 * `Pair`.
 
diff --git a/src/Rings/mpoly-ideals.jl b/src/Rings/mpoly-ideals.jl
index 629681cc028c..6f69dd8d0068 100644
--- a/src/Rings/mpoly-ideals.jl
+++ b/src/Rings/mpoly-ideals.jl
@@ -1203,17 +1203,27 @@ function minimal_primes(
 
   # This will in many cases lead to an easy simplification of the problem
   if factor_generators
-    J = typeof(I)[ideal(R, elem_type(R)[])]
+    J = [ideal(R, gens(I))] # A copy of I as initialization
     for g in gens(I)
       K = typeof(I)[]
       is_zero(g) && continue
       for (b, k) in factor(g)
+        # Split the already collected components with b
         for j in J
           push!(K, j + ideal(R, b))
         end
       end
       J = K
     end
+
+    unique_comp = typeof(I)[]
+    for q in J
+      is_one(q) && continue
+      q in unique_comp && continue
+      push!(unique_comp, q)
+    end
+    J = unique_comp
+    
     # unique! seems to fail here. We have to do it manually.
     pre_result = filter!(!is_one, vcat([minimal_primes(j; algorithm, factor_generators=false) for j in J]...))
     result = typeof(I)[]
@@ -2110,7 +2120,8 @@ function small_generating_set(
   computed_gb = IdealGens(ring, sing_gb, true)
   if !haskey(I.gb,computed_gb.ord)
   # if not yet present, store gb for later use
-    I.gb[computed_gb.ord] = computed_gb
+    I.gb[computed_gb.ord]      = computed_gb
+    I.gb[computed_gb.ord].isGB = true
   end
 
   # we do not have a notion of minimal generating set in this context!
@@ -2328,4 +2339,3 @@ end
 function hash(I::Ideal, c::UInt)
   return hash(base_ring(I), c)
 end
-
diff --git a/src/Serialization/Fields.jl b/src/Serialization/Fields.jl
index 4176250d0e58..043ff7c23184 100644
--- a/src/Serialization/Fields.jl
+++ b/src/Serialization/Fields.jl
@@ -191,7 +191,7 @@ function save_object(s::SerializerState, K::FqField)
     save_object(s, order(K))
   else
     save_data_dict(s) do
-      save_typed_object(s, defining_polynomial(K))
+      save_typed_object(s, defining_polynomial(K), :def_pol)
     end
   end
 end
@@ -202,7 +202,7 @@ function load_object(s::DeserializerState, ::Type{<: FqField})
       order = ZZRingElem(node)
       return finite_field(order)[1]
     else
-      def_pol = load_typed_object(s)
+      def_pol = load_typed_object(s, :def_pol)
       return finite_field(def_pol, cached=false)[1]
     end
   end
diff --git a/src/Serialization/Upgrades/1.2.1.jl b/src/Serialization/Upgrades/1.2.1.jl
new file mode 100644
index 000000000000..3e33f35c831f
--- /dev/null
+++ b/src/Serialization/Upgrades/1.2.1.jl
@@ -0,0 +1,24 @@
+push!(upgrade_scripts_set, UpgradeScript(
+  v"1.2.1",
+  function upgrade_1_2_1(s::UpgradeState, dict::Dict)
+    upgraded_dict = dict
+    if haskey(dict, :_type) && dict[:_type] == "FqField"
+      if dict[:data] isa Dict
+        if !(haskey(dict[:data], :def_pol))
+          upgraded_dict[:data][:def_pol] = copy(dict[:data])
+        end
+      end
+    elseif haskey(dict, :data) && dict[:data] isa Dict
+      upgraded_dict[:data] = upgrade_1_2_1(s, dict[:data])
+    end
+    if haskey(dict, :_refs)
+      upgraded_refs = Dict()
+      for (k, v) in dict[:_refs]
+        upgraded_refs[k] = upgrade_1_2_1(s, v)
+      end
+      upgraded_dict[:_refs] = upgraded_refs
+    end
+
+    return upgraded_dict
+  end
+))
diff --git a/src/Serialization/Upgrades/main.jl b/src/Serialization/Upgrades/main.jl
index fa297ff5e03f..40c9f321aa08 100644
--- a/src/Serialization/Upgrades/main.jl
+++ b/src/Serialization/Upgrades/main.jl
@@ -141,6 +141,7 @@ include("0.13.0.jl")
 include("0.15.0.jl")
 include("1.1.0.jl")
 include("1.2.0.jl")
+include("1.2.1.jl")
 
 const upgrade_scripts = collect(upgrade_scripts_set)
 sort!(upgrade_scripts; by=version)
diff --git a/test/Combinatorics/EnumerativeCombinatorics/tableaux.jl b/test/Combinatorics/EnumerativeCombinatorics/tableaux.jl
index c3f539917395..16d1f844c703 100644
--- a/test/Combinatorics/EnumerativeCombinatorics/tableaux.jl
+++ b/test/Combinatorics/EnumerativeCombinatorics/tableaux.jl
@@ -6,9 +6,9 @@
   @test reading_word(young_tableau(Array{Int,1}[])) == Int[]
 
   # weight
-  @test weight(young_tableau([[1,2,3],[1,2],[1]])) == [3,2,1]
+  @test weight(young_tableau([[1,2,3],[2,3],[3]])) == [1,2,3]
   @test weight(young_tableau([[1,2,3,4,5]])) == [1,1,1,1,1]
-  @test weight(young_tableau([[1],[1],[1]])) == [3]
+  @test_throws  ArgumentError  weight(young_tableau([[1],[1],[1]]))
   @test weight(young_tableau(Array{Int,1}[])) == Int[]
 
   # is_standard
diff --git a/test/Combinatorics/Matroids/Matroids.jl b/test/Combinatorics/Matroids/Matroids.jl
index 94474e845106..5cd0f76521dc 100644
--- a/test/Combinatorics/Matroids/Matroids.jl
+++ b/test/Combinatorics/Matroids/Matroids.jl
@@ -422,10 +422,17 @@
   @testset "matroid_hex" begin
     M = fano_matroid() 
     N = uniform_matroid(2, 4)
+    NN = uniform_matroid(1, 4)
 
     M1 = matroid_from_matroid_hex(matroid_hex(M)) 
     N1 = matroid_from_matroid_hex(matroid_hex(N))
+    NN1 = matroid_from_matroid_hex(matroid_hex(NN))
+
     @test is_isomorphic(M, M1)
     @test is_isomorphic(N, N1)
+
+    @test matroid_hex(NN) == "r1n4_f"
+    @test is_isomorphic(NN, NN1)
+
   end
 end
diff --git a/test/Groups/subgroups_and_cosets.jl b/test/Groups/subgroups_and_cosets.jl
index abf2fcea09b9..298fc50958c0 100644
--- a/test/Groups/subgroups_and_cosets.jl
+++ b/test/Groups/subgroups_and_cosets.jl
@@ -1,29 +1,41 @@
 @testset "Subgroups" begin
-   G = symmetric_group(7)
-   x = cperm(G,[1,2,3,4,5,6,7])
-   y = cperm(G,[1,2,3])
-   z = cperm(G,[1,2])
-
-   H,f=sub(G,[x,y])
-   K,g=sub(x,y)
-   @test H isa PermGroup
-   @test H==alternating_group(7)
-   @test domain(f)==H
-   @test codomain(f)==G
-   @test [f(x) for x in gens(H)]==gens(H)
-   @test (H,f)==(K,g)
-   @test is_subset(K, G)
-   flag, emb = is_subgroup(K, G)
-   @test flag
-   @test g == emb
-   @test g == embedding(K, G)
-   @test K === domain(emb)
-   @test G === codomain(emb)
-   @test is_normal_subgroup(H, G)
-   H,f=sub(G,[x,z])
-   @test H==G
-   @test f==id_hom(G)
+   S = symmetric_group(7)
+   Sx = cperm(S, [1, 2, 3, 4, 5, 6, 7])
+   Sy = cperm(S, [1, 2, 3])
+   Sz = cperm(S, [1, 2])
+
+   for T in [PermGroup, FPGroup]
+     iso = isomorphism(T, S)
+     G = codomain(iso)
+     x = iso(Sx)
+     y = iso(Sy)
+     z = iso(Sz)
+
+     H, f = sub(G, [x, y])
+     K, g = sub(x, y)
+     @test H isa Oscar.sub_type(T)
+     @test domain(f) == H
+     @test codomain(f) == G
+     @test [f(x) for x in gens(H)] == gens(H)
+     @test (H, f) == (K, g)
+     @test is_subset(K, G)
+     flag, emb = is_subgroup(K, G)
+     @test flag
+     @test g == emb
+     @test g == embedding(K, G)
+     @test K === domain(emb)
+     @test G === codomain(emb)
+     @test is_normal_subgroup(H, G)
+     H, f = sub(G, [x, z])
+     @test H == G
+     @test f == id_hom(G)
+   end
 
+   G = symmetric_group(7)
+   x = cperm(G, [1, 2, 3, 4, 5, 6, 7])
+   y = cperm(G, [1, 2, 3])
+   H, f = sub(G, [x, y])
+   @test H == alternating_group(7)
    @test !is_subset(symmetric_group(8), G)
    @test_throws ArgumentError embedding(symmetric_group(8), G)
 
diff --git a/test/NumberTheory/nmbthy.jl b/test/NumberTheory/nmbthy.jl
index f4e628df5ccc..bc6790ac17a3 100644
--- a/test/NumberTheory/nmbthy.jl
+++ b/test/NumberTheory/nmbthy.jl
@@ -4,7 +4,8 @@ using Test
 function evalu(x::Fac)
   return x.unit * prod(p*k for (p,k) = x.fac)
 end
-@testset "Polymake.factorizations" begin
+
+@testset "factorizations" begin
   k, a = quadratic_field(-5)
   zk = maximal_order(k)
   f = factorizations(zk(6))
@@ -12,7 +13,7 @@ end
   @test all(x -> evalu(x) == 6, f)
 end
 
-@testset "Polymake.norm_equation" begin
+@testset "norm_equation.absolute" begin
   k, a = wildanger_field(3, 13)
   zk = maximal_order(k)
   na = norm(rand(zk, 1:10))
@@ -20,6 +21,18 @@ end
   @test all(x->norm(x) == na, s)
 end
 
+@testset "norm_equation.relative" begin
+  L, _ = quadratic_field(-1)
+  _, x = L[:x]
+  f = x^3 - 2;
+  k, _ = number_field(f)
+
+  zk = maximal_order(k)
+  na = norm(rand(zk, 10))
+  s = norm_equation(zk, na)
+  @test all(x->norm(x) == na, s)
+end
+
 @testset "DiscreteLog" begin
 
   F = GF(3,4);
diff --git a/test/Rings/mpoly.jl b/test/Rings/mpoly.jl
index 8c81bdd1d30b..1f9c33a9dcae 100644
--- a/test/Rings/mpoly.jl
+++ b/test/Rings/mpoly.jl
@@ -159,7 +159,6 @@ end
   l = minimal_primes(i, algorithm=:charSets)
   @test length(l) == 2
   @test l[1] == i1 && l[2] == i2 || l[1] == i2 && l[2] == i1
-
   R, (a, b, c, d) = polynomial_ring(ZZ, [:a, :b, :c, :d])
   i = ideal(R, [R(9), (a+3)*(b+3)])
   i1 = ideal(R, [R(3), a])
@@ -232,6 +231,19 @@ end
   R, (x, y) = polynomial_ring(QQ, [:x, :y])
   I = ideal(R, [one(R)])
   @test is_prime(I) == false
+  
+  J = ideal(R, [x*(x-1), y*(y-1), x*y])
+  l = minimal_primes(J)
+  @test length(l) == 3
+  
+  QQt, t = QQ[:t]
+  kk, a = extension_field(t^2 + 1)
+  
+  R, (x, y) = kk[:x, :y]
+  J = ideal(R, [x^2 + 1, y^2 + 1, (x - a)*(y - a)])
+  l = minimal_primes(J)
+  @test length(l) == 3
+
 end
 
 @testset "Groebner" begin
@@ -601,4 +613,3 @@ end
   I = ideal(P, elem_type(P)[])
   @test !radical_membership(x, I)
 end
-
diff --git a/test/Serialization/loading.jl b/test/Serialization/loading.jl
index 299688d5f1b3..346bcd4b4245 100644
--- a/test/Serialization/loading.jl
+++ b/test/Serialization/loading.jl
@@ -1,17 +1,25 @@
 @testset "loading" begin
-    
-    @testset "loading Vector{LinearProgram}" begin
-        c = cube(3)
-        LP0 = linear_program(c, [2,2,-3])
-        LP1 = linear_program(c, [2,2,4])
-        v = [LP0, LP1]
-        loaded = load(joinpath(@__DIR__,"vlp.json"))
-        @test length(v) == length(loaded)
-        @test feasible_region(loaded[1]) == feasible_region(loaded[2])
-        @test feasible_region(loaded[1]) == feasible_region(LP0)
-        @test objective_function(loaded[1]) == objective_function(v[1])
-        @test objective_function(loaded[2]) == objective_function(v[2])
-        @test optimal_value(loaded[1]) == optimal_value(v[1])
-        @test optimal_value(loaded[2]) == optimal_value(v[2])
-    end
+  @testset "loading file format paper example" begin
+    F = GF(7, 2)
+    o = gen(F)
+    Fyz, (y, z) = F[:x, :y]
+    load(joinpath(@__DIR__,"polynomial-example.mrdi");)
+    loaded = load(joinpath(@__DIR__,"polynomial-example.mrdi"); params=Fyz)
+    @test loaded == 2*y^3*z^4 + 5*o*y + (o + 3)*z^2 + 1
+  end
+
+  @testset "loading Vector{LinearProgram}" begin
+    c = cube(3)
+    LP0 = linear_program(c, [2,2,-3])
+    LP1 = linear_program(c, [2,2,4])
+    v = [LP0, LP1]
+    loaded = load(joinpath(@__DIR__,"vlp.json"))
+    @test length(v) == length(loaded)
+    @test feasible_region(loaded[1]) == feasible_region(loaded[2])
+    @test feasible_region(loaded[1]) == feasible_region(LP0)
+    @test objective_function(loaded[1]) == objective_function(v[1])
+    @test objective_function(loaded[2]) == objective_function(v[2])
+    @test optimal_value(loaded[1]) == optimal_value(v[1])
+    @test optimal_value(loaded[2]) == optimal_value(v[2])
+  end
 end
diff --git a/test/Serialization/polynomial-example.mrdi b/test/Serialization/polynomial-example.mrdi
new file mode 100644
index 000000000000..0ad82300e7b4
--- /dev/null
+++ b/test/Serialization/polynomial-example.mrdi
@@ -0,0 +1,36 @@
+{
+  "_ns": { "Oscar": [ "https://github.com/oscar-system/Oscar.jl", "1.0.0" ]  },
+  "_type": {
+    "name": "MPolyRingElem",
+    "params": "869a359a-43d3-43f4-9821-0af9346be019"
+  },
+  "data": [[["3", "4"], [["0", "2"]]],
+           [["0", "2"], [["0", "3"], ["1", "1"]]],
+	   [["1", "0"], [["1", "5"]]],
+	   [["0", "0"], [["0", "1"]]]],
+  "_refs": {
+    "152ac7bd-e85a-4b36-acc2-743ade2cad4f": {
+      "data": { "base_ring": { "data": "7",  "_type": "FqField"},
+		"symbols": ["x"] },
+      "_type": "PolyRing"
+    },
+    "869a359a-43d3-43f4-9821-0af9346be019": {
+      "data": {
+        "base_ring": "a8309b96-caec-443c-bedb-e23bb0634c14",
+        "symbols": [ "y", "z" ]
+      },
+      "_type": "MPolyRing"  },
+    "a8309b96-caec-443c-bedb-e23bb0634c14": {
+      "data": {
+        "def_pol": {
+	  "data": [["0", "1"], ["2", "1"]],
+          "_type": {
+            "name": "PolyRingElem",
+            "params": "152ac7bd-e85a-4b36-acc2-743ade2cad4f"
+          }
+        }
+      },
+      "_type": "FqField"
+    }
+  }
+}
diff --git a/test/Serialization/upgrades/GF_2.json b/test/Serialization/upgrades/GF_2.json
new file mode 100644
index 000000000000..812d8d1a467c
--- /dev/null
+++ b/test/Serialization/upgrades/GF_2.json
@@ -0,0 +1,11 @@
+{
+  "_ns": {
+    "Oscar": [
+      "https://github.com/oscar-system/Oscar.jl",
+      "1.2.0"
+    ]
+  },
+  "_type": "FqField",
+  "data": "2",
+  "id": "4e298c21-11cb-45f1-bac0-62e2df5e6454"
+}
diff --git a/test/Serialization/upgrades/GF_2_2.json b/test/Serialization/upgrades/GF_2_2.json
new file mode 100644
index 000000000000..51d9a4e6b4da
--- /dev/null
+++ b/test/Serialization/upgrades/GF_2_2.json
@@ -0,0 +1,45 @@
+{
+  "_ns": {
+    "Oscar": [
+      "https://github.com/oscar-system/Oscar.jl",
+      "1.2.0"
+    ]
+  },
+  "_refs": {
+    "15ec4d5e-409d-4e80-a7a2-aa1b22b0db9d": {
+      "_type": "PolyRing",
+      "data": {
+        "base_ring": "4e298c21-11cb-45f1-bac0-62e2df5e6454",
+        "symbols": [
+          "x"
+        ]
+      }
+    },
+    "4e298c21-11cb-45f1-bac0-62e2df5e6454": {
+      "_type": "FqField",
+      "data": "2"
+    }
+  },
+  "_type": "FqField",
+  "data": {
+    "_type": {
+      "name": "PolyRingElem",
+      "params": "15ec4d5e-409d-4e80-a7a2-aa1b22b0db9d"
+    },
+    "data": [
+      [
+        "0",
+        "1"
+      ],
+      [
+        "1",
+        "1"
+      ],
+      [
+        "2",
+        "1"
+      ]
+    ]
+  },
+  "id": "b2e7bf06-d89a-4fea-8bf4-215a61c16ca2"
+}
diff --git a/test/Serialization/upgrades/poly1.0.5.json b/test/Serialization/upgrades/poly1.0.5.json
new file mode 100644
index 000000000000..b26acd897b02
--- /dev/null
+++ b/test/Serialization/upgrades/poly1.0.5.json
@@ -0,0 +1,110 @@
+{
+  "_ns": {
+    "Oscar": [
+      "https://github.com/oscar-system/Oscar.jl",
+      "1.0.5"
+    ]
+  },
+  "_type": {
+    "name": "MPolyRingElem",
+    "params": "f0885e3e-71ff-4813-88fd-7ee05eeb3657"
+  },
+  "data": [
+    [
+      [
+        "3",
+        "4"
+      ],
+      [
+        [
+          "0",
+          "2"
+        ]
+      ]
+    ],
+    [
+      [
+        "1",
+        "0"
+      ],
+      [
+        [
+          "1",
+          "5"
+        ]
+      ]
+    ],
+    [
+      [
+        "0",
+        "2"
+      ],
+      [
+        [
+          "0",
+          "3"
+        ],
+        [
+          "1",
+          "1"
+        ]
+      ]
+    ],
+    [
+      [
+        "0",
+        "0"
+      ],
+      [
+        [
+          "0",
+          "1"
+        ]
+      ]
+    ]
+  ],
+  "_refs": {
+    "f0885e3e-71ff-4813-88fd-7ee05eeb3657": {
+      "_type": "MPolyRing",
+      "data": {
+        "base_ring": "e06a6ac9-954b-4fb7-89c6-f2a25489440e",
+        "symbols": [
+          "y",
+          "z"
+        ]
+      }
+    },
+    "e06a6ac9-954b-4fb7-89c6-f2a25489440e": {
+      "_type": "FqField",
+      "data": {
+        "_type": {
+          "name": "PolyRingElem",
+          "params": "3a66dcbd-bd73-4bb7-8b99-42d9f5177893"
+        },
+        "data": [
+          [
+            "0",
+            "1"
+          ],
+          [
+            "2",
+            "1"
+          ]
+        ]
+      }
+    },
+    "3a66dcbd-bd73-4bb7-8b99-42d9f5177893": {
+      "_type": "PolyRing",
+      "data": {
+        "base_ring": "221dfa92-69df-4b5a-8f30-166aafddfaa9",
+        "symbols": [
+          "x"
+        ]
+      }
+    },
+    "221dfa92-69df-4b5a-8f30-166aafddfaa9": {
+      "_type": "FqField",
+      "data": "7"
+    }
+  }
+}
diff --git a/test/Serialization/upgrades/runtests.jl b/test/Serialization/upgrades/runtests.jl
index 222da8093629..282678fa9a3c 100644
--- a/test/Serialization/upgrades/runtests.jl
+++ b/test/Serialization/upgrades/runtests.jl
@@ -27,4 +27,11 @@
     loaded = load(joinpath(@__DIR__, "file_version_less_than_1.2.0.json"));
     @test loaded isa Dict
   end
+
+  @testset "< 1.2.1 Upgrade" begin
+    load(joinpath(@__DIR__, "GF_2_2.json"));
+    load(joinpath(@__DIR__, "GF_2.json"));
+    Oscar.reset_global_serializer_state()
+    load(joinpath(@__DIR__, "poly1.0.5.json"));
+  end
 end