End-of-line comments in key mappings treated like options

When including a comment on the same line as a custom key mapping, it is treated like an option. Since v2.2.0, you can observe this in the help dialog, where the options of a command are now displayed in parentheses. For example, using the key map definition map ' Marks.activateGotoMode " alias for backtick:

According to this comment on #3839, this is supposed to be a feature, not a bug:

a "#" which is not at the start of a line doesn't mean a comment, but will be treated as an option of the mapping.

I think this is unintuitive, as the key map syntax closely resembles Vim's, where end-of-line comments are treated as such. At the very least, this is badly documented behavior: The example shown next to the key mappings input field does not make it clear a new line is necessary. Only when the end-of-line comment is included on an unmap line, you get a warning, since its syntax doesn't allow any options.

While I would like to see working end-of-line comments, I can understand if this will not be changed for simplicity's sake, but it would be great to see this behavior clearly documented somewhere.

Reproduce the behavior with the map ' Marks.activateGotoMode " alias for backtick example, then inspect the key-mapping parser and the key mappings input-field example. Done means either end-of-line comments no longer appear as mapping options in the help dialog, or the required comment syntax is clearly documented, including the unmap case.