Created attachment 368658 [details, diff] a cargo-cult patch that seems to fix the problem Under certain conditions, SDL_PollEvents seems to be unexpectedly dropping KEYUP events if an IME is active. The exact conditions are not clear - while it's related to SDL_EnableUNICODE flips, it doesn't happen every time. Both apps where I could trigger this problem (as an input freeze) are not in the tree. The attached patch is a cargo-cult of a recent change in SDL2 made to a similar code block (https://hg.libsdl.org/SDL/rev/713c6a333c33). I can't tell if this is a proper fix. Upstream bug has been filed on 24.12, no response from upstream yet. This is filed basically for *other* distros to take notice. Perhaps someone from x11 herd could shed some light on specifics of interaction between XFilterEvent and xlib keyboard focus ?
Created attachment 369020 [details, diff] patch corrected for an obvious problem As expected, the previous patch was somewhat broken in (in the hindsight) an obvious place. That didn't affect the original problem, but broke other things. This version has that new problem corrected.
Upstream has accepted the patch...without any discussion. :sigh: I can't say I'm really happy with that, but at least things seem to be working now.
added in libsdl-1.2.15-r9