What does autocompletion work for? The tags in your hand made tags file? And for symbols in the current open file?
With ```tag_parser=FreeBasic``` - yes and yes, without ```tag_parser``` - no and yes.
What do you mean by "garbage", maybe post a picture, and the source that caused it.
With ```tag_parser=FreeBasic``` - single comments (at the beginning of the line) and some FreeBasic keywords.  (Символы == Symbols)
The tags file doesn't use the parser, it just needs a language defined to connect the tags structures in memory to.
I don't understand. Without CTags parser? How can I do this? Does Geany do it automatically?
First check if a parser exists in Universal ctags
I didn't find :( (I checked Issues, Pull requests, Exuberant ctags too.)