Thunderbird leaves a “ghost window” on macOS 26

Hi everyone, I’ve run into a weird issue with Thunderbird on macOS 26 (Tahoe) and I’m wondering if anyone else has seen this. When I close the main Thunderbird window using Command + W or RedDot Close Button, the window disappears like normal, but something is still left behind. It’s like an invisible or “ghost” window stays on the screen. Because of that, I can’t click anything that was underneath the Thunderbird window. The area is still blocked as if the window never fully closed. If I open Mission Control (F3), I can see an empty tile where the window should be, which confirms that something is still there even though it’s not visible. A few details: • The problem happens every time I close the main window with Command + W • Thunderbird keeps running in the background, but I can’t bring the window back unless I quit the app completely • This only happens with Thunderbird, no other app on macOS 26 has this issue on my machines • On previous macOS versions I never had this problem System info: • macOS 26 (Tahoe), fully updated • Latest stable Thunderbird release • Mac mini M4 and MacBook Air M4 It looks like some kind of window management bug on macOS 26, but only triggered by Thunderbird. Has anyone else experienced this or knows if it’s a known issue? Thanks!