In Minecraft, there is a keybind F3 + F4, which opens the Gamemode Switcher screen.
Steps to reproduce the issue:
Press F3 + F4 on low window resolution (for example: 1366 x 768)
Open minecraft in full window, still holding F3 + F4
See the bug itself. The results of the issue can be seen in the screenshots below
I do not recommend switching from the lowest window resolution to maximum/fullscreen while holding F3 + F4, as it can cause severe FPS drops, system freezing, and even Minecraft crash.
Tested Versions & Effects:
Affects all versions where gamemode switcher exists. (Confirmed in versions 1.21 through 1.21.5)
Causes system freezing and slower rendering in Minecraft.
Environment
Minecraft version: 1.21.5
OS: Windows 10
Java version: 21
GPU: GTX 1050 TI
CPU: Intel(R) Core(TM) i5-4690 CPU
Please do not mark Unreleased Versions as affected. You don’t have access to them yet.
Thank you for your report!
We are tracking this issue in MC-183784, so this ticket is being resolved and linked as a duplicate.
If you would like to add a vote or provide any additional information to the main ticket, it would be appreciated.
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