Fairly simple problem. When restoring a window positoin profile, Opera and Chrome are "moved" to the correct monitor, without actually being moved.
If that sounds self-contradictory, it kind of is. The window is "moved" to the right place, but it doesn't *actually* move until you leave fullscreen mode.
So if you had, say, 10 browser windows in full screen mode, you will end up with 0-10 browser windows still in fullscreen mode, possibly/likely restored to the incorrect montor.
It'd disconcerting to say the least to watch a fullscreen window get moved to the wrong monitor.
But the kicker is, if you leave fullscreen mode, the browser window snaps to the correct monitor. So it was moved. But it doesn't actually move until you leave fullscreen mode.
I know it must bat least be possible to move a browser in fullscreen mode to a monitor -- because DisplayFusion is doing this and moving it to monitors i never use for fullscreen viewing
(background: i have 4 screens all with different qualities - 3 are big, 1 is 4K, 1 is DisplayPort, 1 is VGA, 1 has an autohide taskbar, 2 have a 1-row taskbar and 2 have a 2-row taskbar, 1 has the clock on the left but not the system tray, 1 is in front of me, 2 are ceiling height, 1 is on a coffee table often obscured a bit by things on the table, two can't be turned off -- ever -- without causing windows to rearrange, one has the system tray on the left but not the clock, each one is unique)