Input lag with tap-hold remapping

[bellissimogiorno]

I remapped KEY_SPACE to produce space if tapped, and KEY_ENTER if held, as follows:

input:  space
output: if_tap(key(KEY_SPACE),key(KEY_ENTER),120)

The remapping works, but with immense lag. It feels like input is silently swallowed until I stop typing, then all my keypresses get dumped all at once.

For example, if I were typing this sentence then I would see "For", and then no further would appear until I reach this full stop and pause typing. ... and then the rest of the sentence would appear.

I'm remapping "AT Translated Set 2 keyboard" in Ubuntu 24.04 running Gnome.

I hope the above is clear but if any further information is required I'm happy to provide it. Thank you.

[sezanzeb]

if_tap, unlike mod_tap, doesn't behave this way. Can't reproduce in Ubuntu 24.10 running KDE. I'm tempted to think this is a problem with gnome or some other component of your system.