I just compiled and tested DOSBox with SDL2 support and it fixed random KeyUp events in at least one of the titles I experience the problem (Megarace 2). It also fixed DOSBox alt-tab behaviour and I think mouse movement in-game feels more native (I need to properly test this though). Compiled …

It's rather easy to work around this using SDL environment variables and proper .conf file. I do it automatically in https://github.com/dreamer/boxtron/ to place DOSBox in fullscreen on monitor user prefers. DOSBox really needs to switch to SDL2 by default at this point.

Please note that creators of SDL urge every project to abandon SDL1.2 (which does not receive updates at all at this point) and move to SDL2 - I think it's very likely to be a problem on the interaction between SDL1.2 and desktop environment. I will pick one of patch series implementing SDL2 to …

Good find! I tested all the games in fullscreen mode so far. With TR1 in windowed mode, the problem is not there any more. I guess it's really time to switch to SDL2 and its improved fullscreen handling?

I see this problem in several games in 0.74-2 and can still reproduce it in 0.74-3 (revision 4241). It can be reproduced in practically any game, but sometimes it's quite hard to do so (due to e.g. level design). It's easiest to reproduce in Megarace 2, as it's a racing game and depends on pressing …

There's no way to log in, I can't find information of forum... is it dead?