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CloseReview for CompactHeader by Maëlan
Rated 4 out of 5 stars
This add-on is great, very handy for seeing more of the message in the split view (it only has a small glitch, i.e. occasionally headers are half-collapsed and you have to click on [±] to get back to a consistent state).
Is there any chance that it gets updated for Thunderbird 78? (I guess it’s harder to implement now with WebExtensions?)
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