in the current version 1.19.30 on Android 12 there is a spacebar bug with bluetooth keyboard & Mouse Control:

Steps to Reproduce:

as soon as you move the mouse cursor over a text field (regardless of whether it is in the inventory search field or in chat), minecraft no longer recognizes the space bar in the game.

• you can no longer jump, fly, swim, or assign the button in the menu

 The space bar is still recognized in chat and in the search field.

It can only be fixed with a restart until you move the mouse over a text field again. I'm playing on a galaxy tab s7 with android 12 with bluetooth mouse and keyboard. outside of minecraft the keyboard works fine.