Rated 5 out of 5 stars

This looks like exactly what I need for Thunderbird 78, however, could I request that when/if Lab5 develop this for TB78, that they set the Background Colour to be set, as TB natively sets the text colour but that's not actually very useful for showing folder depth,

I would love it where the folders are coloured by depth, with a background shade for each new level.

(I did look in to the Moz Developer guide on how to make this myself but it's not clear how to access folder tree properties)