I'd like Geany to highlight keywords like "TODO" and "XXX". This is not the default (as in gedit, for example), and there's no configuration list for it, AFAIK.
Keywords are listed in filetype configuration files, `Tools->Configuration files->Filetype Configurations->.....`. If you want you can add them.
That's true! But is it possible to highlight keywords *within* comment blocks? Sorry I wasn't exact enough.
Ahh, that depends on the specific lexer for the language, but its unlikely that any consider the contents of comments in any way.
See also the Geany-plugins add-ons plugin "Tasks" capability.
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