It would be nice if VSCode natively supported inputting git trailers into the it panel in a user-friendly way, just like it does with the subject line, instead of having to put them into the body as free-Form text.

git panel implementation details

• I know, not everyone uses that native git feature, so this could be wrapped in a collapsible section to not take up space by default
• I know, there is some debate about "official" trailers, but there are quite a few commonly agreed upon ones, so these as well as those used in other commits of the repository could be used for input suggestions

possible settings/extendability (probably added as follow-up if considered)

• the input suggestions could be a public API to allow for adding custom suggestions or even pre-filling by extensions (or settings itself; even validation is imaginable, e.g. when there are a couple spellings the same meaning (e.g. Co-author: vs Co-authored-by:))
• the trailers might be configured to be of a certain type (e.g. git user for things like Co-authored by:), so VSCode could also provide auto-complete for the value input (even validation is imaginable when configured by the user or an extension (e.g. "use the full email address format for things like Co-authored by:" (John Doe <john.doe@example.com>))
• it might also be possible to prevent committing when certain trailers configured as required are not set for the commit

things to keep in mind

• some people would probably mix putting trailers into the body AND the trailers section - they probably want them to be merged (principle of least surprise)