@danpla @codebrainz totally agree with both of you, special comment handling is language specific and shouldn't be in Geany core, but it is, and has been for ages, so unless "somebody"[1] wants to make a pull request removing it to a plugin[2] then this is just a change to existing functionality.
And since its a change to existing functionality, which already has a setting in prefs, @danpla has just suggested adding a sub-setting to that existing setting. Although that prefs page is busy, there is space for another line (at least on my font size). So it seems a reasonable solution.
@danpla havn't actually looked at your code
[1] "somebody" in quotes is an olde time convention in Geany meaning "somebody, not necessarily you, but definitely won't be me", blame @eht16 :grin:
[2] an alternative would of course be to make the in-core functionality language agnostic by using the existing and perhaps additional comment settings in filetype files, but "somebody" has to do it