This sounds great, but it seems there's no out-of-the-box support for a rich text textbox?

I have a python script that I want to deploy as self-contained app for windows and osx with a gui. Finding a framework that works, is decent to use, doesn't need hundreds of MBs of dependencies, and has rich text support is...not easy.

Have a look at nuitka for compiling your script to a binary.

Thanks, I'll try it! I was using pyinstaller atm.

I'm still trying to figure out if there's a GUI that supports different text with mixed colors and features out of the box, and that's not horribly broken in OS X

In the old days, you would just go on AOL's Windows programming section, find a shareware rich text control, and use that.

In the old days, I would do it in Delphi and have the controls already in my toolbox :)

I was actually thinking of giving it a go, but the idea of a Python backend and a Delphi frontend is as attractive as recoding everything in ASM.