Alert shortcode placed right after code block w/ line numbers is being rendered incorrectly

[jwadolowski]

Issue description

I've recently noticed that alert shortcode placed right after a code block (w/ line numbers enabled, that's important) results in 2 elements being glued together (there's no vertical space between them, see screenshot below).

Steps to reproduce

1. hugo new site alert-test --format yaml
2. cd alert-test && hugo mod init foo
3. hugo new content content/test.md
4. mkdir -p config/_default && mv hugo.yaml config/_default
5. Add config/_default/module.yaml with the following contents:

imports:
  - path: github.com/jpanther/congo/v2

6. echo "colorScheme: ocean" > config/_default/params.yaml (optional, applies to all colorschemes)
7. Update content/test.md content so it looks like this gist
8. hugo server

Current state

Expected state

Vertical space is rendered between alert and code block.

Noteworthy facts

1. The issue occurs only when linenos option is used inside code fences

Theme version

v2.10.0

Hugo version

hugo v0.140.2+extended+withdeploy darwin/arm64 BuildDate=2024-12-30T15:01:53Z VendorInfo=brew

Which browser rendering engines are you seeing the problem on?

Chromium (Google Chrome, Microsoft Edge, Brave, Vivaldi, Opera, etc.), Firefox (Mozilla Firefox), WebKit (Safari)

URL to sample repository or website

No response

Hugo output or build error messages

N/A

[jwadolowski]

Actually, there's a few more combinations that result in missing vertical spacing:

1. code block (w/ numbers) + button
2. code block (w/ numbers) + button + mermaid