Mouse input not working at all in Minecraft for Windows v1.21.124 (title screen and in-game)

This issue is 100% reproducible and occurs every time I launch the game.

After updating to Minecraft for Windows version 1.21.124, I encountered a critical issue where the mouse becomes completely unresponsive throughout the entire game. The cursor is visible, but I cannot click or interact with any UI elements — not only on the title screen, but also after entering a world. Keyboard and controller input still work, but the mouse has no effect whatsoever.

I tested multiple mice, including a Logitech G502 X LIGHTSPEED (wireless) and a basic wired USB mouse. Both work perfectly in other applications but fail to function in Minecraft. I also uninstalled Minecraft for Windows via the Minecraft Launcher and reinstalled it, but the issue persisted.
This problem occurs only in the official release version 1.21.124. The same system runs the Preview version without any issues, and the Java Edition also works fine. This suggests the issue is specific to the Bedrock version in this release.

I use a dual monitor setup and tested the game on both screens. The problem occurs regardless of which monitor is used.

This issue renders the game completely unplayable with a mouse, which is a serious accessibility and usability concern. I sincerely hope this can be addressed in an upcoming hotfix.