And this file is missing in your patch :).

sorry, I should have think to this.

It's probably easier to attach it alone with this message now (see txt2tags.c).

I'm just wondering whether it isn't possible to extend the Markdown parser to parse txt2tags files as well.

it's problably possible because the txt2tags tags don't interfere with the markdown for this part. But...

This way we wouldn't need to add yet another filetype in Geany.

yet the extension for txt2tags files is different. And in case I or someone manage to write the scintilla lexer, the rest of the txt2tags syntax would interfere with the markdown one.

Your patch doesn't list any changes to Scintilla code,

I didn't include it, maybe I could have done it (without the scintilla lexer)? I'm still not satisfied with my scintilla lexer, because I managed only to highlight the tags and not the text. I'll propose it in a later revision.

Besides, the first time I inserted my changes, I did it on the released version 0.18, so I had to do it again with the svn version later.