Perhaps the problem isn't only related to applications run via launcher. And yes, I looked through possible answers first.
In Ubuntu 16.04.5, the apps I started via sidebar launchers, remembered their window sizes (and mostly positions,a s well).
In Ubuntu 18.04.2 (fresh installation), they are always started full-screen, no matter what. Is it possible to configure Gnome to remember at least last known windows size, as it was in 16.04.5 ?
I'd rather not use crutches like devilspie. The last thing I wish to do is replacing every launcher with wrappers.