Window becomes small when switching between 1080p and 4k monitors

[rogi]

My laptop has 1080p screen resolution and I often connect it to 4K monitor.
So when I connect to 4k monitor and open some image in XnView MP, the window opened is very small, like 200x300 pixels or so.
Same when I open XnView on 1080p screen after previously opening it on 4K screen.

[xnview]

even if you restart XnViewMP?

[user0]

this also happens when you change win DPI scale to 100% from any other value (on 4k monitor)

1. set win DPI scale to 150%
2. open any image in Viewer, resize window, close app
3. set win DPI scale to 100%
4. open any image in Viewer
app window will be resized to ~200x200px

[rogi]

This happens only first time when I use monitor with different resolution and different system scaling accordingly.
Probably has something to do with resolution and scaling.
I have a system scale set to 150% for 4K monitor, which I plug to the laptop. So when I use the built-in 1080p screen and open XnViewMP, the app's windows is very small and I have to maximize it. All consecutive launches are OK, only the first one if affected after I switch monitors. In other words, it happens only once but every time when resolution/scale is changed.

[simon]

Same issue for me (on windows 10) when switching between the screen of the laptop (HD, 125%) and a big TV screen (UHD, 100%). Not only the windows becomes tiny but once the whole windows has been re-established to the full screen, the relative sizes of the various panes of the browser (tree pane, preview pane, thumbnail pane) are not kept. Fortunately, it is easy to work around this issue by attributing a layout to the laptop screen and another one to the UHD screen, and then using "restore" one or the other (it is a bit strange to have to save 2 layouts for the same display, but this works)