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CloseReview for Colored Folders by mmelcot
Rated 5 out of 5 stars
This was indeed a nice add-on.
I was also disappointed to see it is not supported by Thunderbird > 73
But I just discovered that from Thunderbird 78, you can now set the folder color with a builtin functionality:
https://www.ghacks.net/2020/07/16/a-look-at-some-of-the-changes-in-thunderbird-78/
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