unspecified-javascript.yml

draft_date: 2025-02-20
name: Unspecified JavaScript
description: Some browsers implement unspecified JavaScript properties or methods. This is an artificial feature that contains references to browser compatibility data entries for those additions.
spec: https://web-platform-dx.github.io/unspecified/
discouraged:
  according_to:
    - https://web-platform-dx.github.io/unspecified/
compat_features:
  # Firefox-only Function property.
  # There exists some discussion of getting rid
  # of it: https://github.com/tc39/proposal-error-stacks/issues/14
  - javascript.builtins.Function.displayName

  # Firefox-only InternalError object
  # Thrown on "too much recursion" while Safari and Chrome throw RangeError
  # https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Errors/Too_much_recursion
  - javascript.builtins.InternalError
  - javascript.builtins.InternalError.InternalError

  # Firefox-only Error properties
  - javascript.builtins.Error.Error.lineNumber_parameter
  - javascript.builtins.Error.lineNumber
  - javascript.builtins.Error.Error.fileName_parameter
  - javascript.builtins.Error.fileName
  - javascript.builtins.Error.columnNumber

  # Error.prototype.stack is a candidate for future standardization
  # https://github.com/tc39/proposal-error-stacks
  - javascript.builtins.Error.stack