I use Manjaro Stable with KDE, on a Lenovo T480s with an external monitor (that has a significantly higher resolution).
Thunderbird seems to have now decided that the minimum horizontal size will be significantly larger than my laptop screen, even when my external monitor is disconnected. My wild guess is that this is some percentage of the resolution of my external monitor. When I maximize Thunderbird on my laptop part of the window disappears, in the example below you see the list of accounts are too far on the left side. You also see here the relative difference in screen size (the screenshot of leaves on top is the external monitor).
I assume that deleting all configs for Thunderbird will probably resolve the issue, but I would prefer not having to do so (it takes time to reconfigure and honestly in my mind that should be a last resort solution to an application which is considered stable).
I also have Thunderbird beta installed, and do not experience the issue there.
Hmm, I am not so convinced that’s fully true (at least for the mid term future). This happened without any application update (as far as I can see), and the stable version (68.12) is way behind the “official stable” (78.3) and the beta package I am talking about (82.0b1). Thunderbird package for Manjaro stable was last updated on Aug. 29th, and I use it every day so I think I would have noticed (but yeah, until I find the issue I cannot deny that’s a possibility).
As magically as it arrived, the issue also disappeared a few days later (approx one week). I am still on 68.12.
Maybe something to do with disconnecting from external monitor “in the wrong order”. I have also noticed e.g. Zoom gets really confused about resolutions on multiple screens, but that seems very consistent.