Compose key and input method confusion, custom compose config stopped working after update

I’ve been using the Compose key for special characters for quite a while now, including a quite rich custom ~/.XCompose file. There has always been a problem, where the Compose key didn’t register at all in QT-based applications, but I did not mind, as most applications I use to edit text are GTK based.

Now, the behavior of the Compose key has changed in a recent update. Before, after pressing the Compose key there was no feedback until a character was produced. Now, there is a symbol indicating the Compose key followed by underlined characters that you type, which then turn into the desired character (Fig.1). There is one problem however, after this seemingly cosmetic change, the system started ignoring my ~/.XCompose file.

Fig. 1: (the underline is lost due to loss of focus when taking the screenshot)

I’ve been doing all my tests with firefox. I’ve tried manually setting the input method to xim by setting the $GTK_IM_MODULE env variable, which is recommended by some forum posts. This recovers the original behaviour with no feedback until a character is produced, but my .XCompose is still ignored. If I try to read the variable before setting it, it returns:

 $  echo $GTK_IM_MODULE  
 $  echo $QT_IM_MODULE     

I tried to find out what this cedilla input method is, but all Google searches point me to results along the lines of “how to type cedilla with x input method”.

I use i3 and set my keyboard layout at startup using setxkbmap

I would like to somehow load my custom .XCompose config, but I haven’t been able to find out how. (Preferably without

Thank you very much for your assistance.

Setting the $XCOMPOSEFILE env variable also doesn’t work.

I finally found what the problem was, my .XCompose config was invalid, which worked before but doesn’t now. Removing invalid lines from config solved the issue.

Possibly same issue here after updating to Tumbleweed 20211105.

As far as I can tell, I got the original behaviour back by going to KDE Menu → Settings → Hardware → Input Devices → Keyboard → Advanced → Key to choose 3rd level (it’s there twice, the first one) → “Right Alt; Shift+Right Alt as Compose”. Hit Apply and see what happens.

Yeah I don’t use KDE.

As I mentioned above, I was able to solve the problem I had with GTK as zoucan see above.

From what I was able to figure out, Qt had a problem with the config being too long, when I made it shorter, it worked.