Rated 3 out of 5 stars

In the options of this addon I saw a lot of options to change colors of quotes, but:

> You can choose between two quoting display modes:
> graphical quoting with colored bars around quoted
> paragraphs (default), and traditional plain text quoting where
> each quoted line starts with one or more ">" characters.

I tried choosing the "plain text quoting where each quoted line starts with one or more ">" characters" but I didn't find the way.

This review is for a previous version of the add-on (4.0.2). 

If your goal is to have the ">" displayed in front of each line using the colors from QuoteColors, then this won't be working anymore without changing a hidden pref in about:config. The WX API doesn't allow to change these prefs in about:config, which means for QuoteColors, that it can't manage this pref anymore.

You can try to set "mail.quoted_graphical" to false in about:config. Maybe this is, what you are missing.