Plasma’s restore session functionality has started working for me relatively recently, but there’s one thing that bugs me: all my windows are just dumped together into the same activity and workspace I’m in at login, so it becomes a big mess.
Is there a setting somewhere that tells it to respect the last position of the windows?
My understanding is that not saving window size and placement is a limitation of Wayland right now (for security reasons that it’s trying to address rather than ignore like xorg I think?). I think it’s something that’s planned to be added eventually, but who knows when that might be. It is frustrating in the meantime I agree.
Take all this with a large grain of salt of course, I am by no means an expert on the matter and am just repeating what I read when I looked into it myself a year ago or so.
Your are right, it’s not implemented yet in Plasma Wayland. It must be done in Plasma/KWin itself since top-level Wayland windows can’t position themselves on screen and don’t even know their coordinates (and doing it on the application side is not really correct since not all apps will support it and it duplication of work and code, while compositor can do it consistently for all windows). However it just doesn’t work yet.
I have simply created custom rules for the respective programs and the associated open windows. Since these are standard programs anyway, which I always have open or want to open again on the same activity with the same arrangement. So I set up one for gaming, Internet, multimedia and work. This works without any problems.