Comment 10 for bug 1691115

> Do you mean this?
> alex@Lenovo $ export GTK_IM_MODULE=multipress libreoffice
Just this should already do:
GTK_IM_MODULE=multipress libreoffice
I then picked writer and the number pad would switch through multiple letters.
Configuration is in
/etc/gtk-3.0/im-multipress.conf

Is it installed?
ll /usr/lib/x86_64-linux-gnu/gtk-3.0/3.0.0/immodules | grep multipress
-rw-r--r-- 1 root root 15K Mai 1 05:03 im-multipress.so

It's from the libgtk-3-0 package, so it probably is.

Does it work in gedit?
GTK_IM_MODULE=multipress gedit

If yes then there might be something iffy about libreoffice in Mint.