Hi. First of all, thank you for a greatest plugin ever.
Is it possible to force some folders/files icons to be colored with custom color? It will help to make accent on it.
Yes. The steps are documented in the readme.
Just replace &[data-name=".git"] with `&[data-name$="your-folder-name"] and assign the colours in your user stylesheet.
Thank you.
IMHO, it would be great to change icon color using context menu (right click)
Uh, no, that would be going way too far. That's the responsibility of a stylesheet. :-)