Screen flickers/flashes when interacting with UI controls when full-screen/maximized (Windows 10)

[CheeseTurtle]

Describe the bug
When clicking buttons that open a popup menu or dialog, the screen momentarily flashes what appears to be totally black. (It happens very quickly.) This is distracting and jarring and makes RNote extremely unpleasant to use. The flickering also occurs when closing/dismissing these menus/dialogs. Essentially, there is a conspicuous whole-screen flicker when showing or hiding any menu / dialog.

To Reproduce
Steps to reproduce the behavior:

1. Ensure the RNote application is in full-screen mode, or that the application window is maximized.
2. Trigger the opening of a menu or dialog. Examples of how to do this include, but are not limited to:
   • Click the "gear" button in the tool palette (or really anything in the tool palette that triggers a dialog or menu).
   • Open the Settings in the left sidebar and begin configuration of the Regular Cursor.
   • Open the application menu by clicking the hamburger-menu icon in the upper-right corner.
   • Open the "Pick a Color" dialog.
   • Alternatively, perform any of the above actions and then dismiss the popup (by making a selection [in the case of a menu], by re-pressing the button that was used to summon the popup [in the case of a dialog], etc).
3. Observe flickering.

Expected behavior
No flickering should occur whatsoever. It is forgivable when entering/exiting full-screen mode, but interactions with UI controls should not produce this effect.

Console Output

Run the app in the terminal with flatpak --env=RUST_LOG=rnote=debug --env=RUST_BACKTRACE=1 run com.github.flxzt.rnote and post the output.

Does this apply on Windows? I do have WSL but I'm not using it to run RNote.

Screenshots

Based on the screencap, it appears that the perceived flicker effect is the result of briefly opening and then immediately closing the application switch HUD (manually accessible via alt + (shift + ) tab).

Desktop:

• OS: Windows 10.0.19045
• App Version: Rnote v0.9.4
• Installation Source: msi, I believe
• Input Source: Triggered separately by mouse, keyboard, and Wacom One

[Intranox]

Personally, full screen mode has never worked well in Windows but I can say that with the window maximized I don't notice any problems, not even by following the steps described. However, I want to make an observation in this regard: many of the graphic problems strictly linked to the UI depend on gtk4 in Windows, until last week with gtk 4.14.2 an annoying bug was finally resolved for me which did not allow me to minimize the app by clicking on the icon in the taskbar. Unfortunately I understand that it will be some time before gtk version 4.14.2 is actually implemented on Rnote

[camradex]

i'm having the same issue under the same conditions, however i wasn't able to record it because it produces an error on xbox game bar and snipping tool whenever i maximize the app