I used the default lxqt desktop settings to set the background image and set it to stretch I tried every setting including tiling and it still didn’t fill the entire screen. It’s on actual hardware not vm.
I did see a bug for it on the vm side when I checked the bug reports but didn’t really see much on the physical hardware side. The reason I’m having this bug is because I’m hooking it into a TV and by default the wm tries to auto-set the resolution. In this case it set it to 800x600 which looks bad on a big screen.
I tried setting it to a different resolution and it set everything but the wallpaper didn’t scale up with everything else. I’ve tried the same under openbox and no issue it seems to be a lxqt issue. I have tried kwin as well and it didn’t fix the issue.