Here's a fragment of event_stream_next_event(): #if 0 /* Do this if the poll-for-quit timer seems to be taking too much CPU time when idle ... */ reset_poll_for_quit (); #endif event_stream->next_event_cb (event); #if 0 init_poll_for_quit (); #endif I was going to slow down quit polling on Windows, but reading the code found that this was implemented on global level, but later ifzeroed. Does this break something? A problem is not with CPU time, as the comment claims. The real problem is that idle XEmacs still runs every tick, so cannot completely swap out. I do not see any CPU consumption, but there's needless physical RAM consumption with idle XEmacs. I can easily enable this for Windows only; my question is were there any serious reasons to disable that code, or it has been just considered useless? I cannot find any changelog for it, so the change looks antemundane... Kirill