After the 1.21.121 patch, there is a problem with Minecraft Bedrock not locking the mouse pointer to the center of the screen when entering a GUI.
To reproduce the issue: first open a chest and observe where the mouse pointer is on the screen. Now close the chest, and turn about 90 degrees either left or right and open another chest. You will see the mouse pointer on the far side of either the left or right of the screen, depending on the way you turned the camera. You will also observe that even with the mouse on the far side of the screen, the first item is highlighted in the center GUI screen with the name of the first object in the GUI appearing in random places on the screen (in the video, you will see the name Stone on the right of the 2nd chest GUI after turning the camera). This is a new bug that showed up after Hotfix 1.21.121 and was not present in previous versions.
Expected Result: To return the mouse pointer functionality to what is was pre 1.21.121 hotfix. That is, when you open a GUI, the mouse is centered in the screen again and not moved to a random location on the screen based upon how you moved the camera just before opening the GUI.
Whoarus
After the 1.21.121 patch, there is a problem with Minecraft Bedrock not locking the mouse pointer to the center of the screen when entering a GUI.
To reproduce the issue: first open a chest and observe where the mouse pointer is on the screen. Now close the chest, and turn about 90 degrees either left or right and open another chest. You will see the mouse pointer on the far side of either the left or right of the screen, depending on the way you turned the camera. You will also observe that even with the mouse on the far side of the screen, the first item is highlighted in the center GUI screen with the name of the first object in the GUI appearing in random places on the screen (in the video, you will see the name Stone on the right of the 2nd chest GUI after turning the camera). This is a new bug that showed up after Hotfix 1.21.121 and was not present in previous versions.
Expected Result: To return the mouse pointer functionality to what is was pre 1.21.121 hotfix. That is, when you open a GUI, the mouse is centered in the screen again and not moved to a random location on the screen based upon how you moved the camera just before opening the GUI.