I can’t give an authoritative response here, as I’m not using 22.04 currently, nor do I know which LXQt you’re using (ie. the older version it installs with, or new backport that is available).
I have a panel (using quicklaunch) on the left side of my screen, like Ubuntu Unity introduced with Ubuntu 11.04, where I’ve put my regularly used apps as quick to open icons; a picture of what it looked like back in June 2019 can be seen here; it’s on my lower screen & hides when the pointer isn’t hovering over it.
By right-clicking on the feathepad icon I’m offered a choice of
- Featherpad (text editor)
- New Window
- Standalone window
The first option opens a new tab in my existing window (featherpad is almost always open in my normal usage), where as the other two options will open a new document in other windows.
If I use the “New Window” option, the second window is still running using the existing featherpad processes, where as if I select Standalone I’ll note another process running, ie.
guiverc@dc780:~$ ps -elf |grep feather
0 S guiverc 127869 118150 0 80 0 - 201596 do_sys 08:22 ? 00:00:02 /usr/bin/featherpad
0 S guiverc 146117 118150 13 80 0 - 163612 do_sys 10:37 ? 00:00:00 /usr/bin/featherpad --standalone
0 S guiverc 146123 123419 0 80 0 - 1584 pipe_r 10:37 pts/0 00:00:00 grep feather
All of this is using the default LXQt from upstream, but I’ve not currently got the time to boot a 22.04 system and see if it’s available using the standard (older) LXQt that came with 22.04, nor the newer LXQt that’s available in backports; however I’d hope it would available using the backports version of LXQt. (My default systems runs the development release, what is currently lunar with a newer featherpad; so even if not available on 22.04 - what I describe will be on Lubuntu 23.04)