When you enable customizable controls experiment, it doesn't show the buttons like "Reset Default", "Done", "Size" or "Opacity", which means that any changes you make won't be made and pressing back on your phone causes UI to bug out when going back into the game.
Steps to reproduce:
Import and enable the attached resource pack:
Enable Customizable Controls (Experimental) in Settings -> Controls -> Touch
Create/open a world
Go to Customize controls in Settings -> Controls -> Touch. Observe that there are no options
Exit the Customize controls UI
Observed result:
There are no options when entering the Customize controls UI. After exiting the Customize controls UI you are unable to re-enter it; the information pop-up says "There is already a touch control customization screen open".
Expected result:
While there being no options might be expected due to the resource pack being outdated, the Customize controls UI does not break after entering it for the first time.
Attachments
Comments 6

Thank you for your report!
However, this issue has been temporarily closed as Awaiting Response.
You seem to be using resource packs in your world. Does the issue persist if you turn them off? If yes, then what is the model of your device?
This ticket will automatically reopen when you reply.
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Well it's fine without resource packs, but then that means you lot need to add support for resource packs, same with the experimental respawn screen, which doesn't actually occur at all for me anyway
Could you please attach a resource pack with which the issue can be observed?
This ticket will automatically reopen when you reply.