Developer reply by Philippe V.
Rated 5 out of 5 stars
This addon is great, but there is a visual problem. Some panels are using the system theme instead of your chosen thunderbird theme and it ends up looking very weird. Example: https://i.imgur.com/VqnVIDG.jpg
This is happening in Linux but maybe it also happens on Windows, but since default Windows theme is similar to the theme of Thunderbird it doesn't look so weird on Windows.
which theme do you use ? I don't have this on Ubuntu... (cardbook (at) cardbook.icu)
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