I recently upgraded to Thunderbird 128, and now I have very strange things happen when I filter messages. After I type one or two or sometimes three characters into the Filter field Thunderbird freezes. If I continue typing the additional characters don't appear in Filter, nothing happens in filtering, and my mouse cursor disappears when it is in the Thunderbird window (it appears normally if outside the window). After several seconds everything starts working OK, and my messages get filtered.

So, in the end I can filter messages, but this freezing is frustrating and a waste of time.