(*This issue is being resolved, but you can still read the information of this issue.)

In Minecraft Pocket Edition 1.19.50.23 Beta/Preview, when riding Bamboo Rafts or Wooden Boats (also with chests) with the old control UI selected, the new control UI will overlay within the old boat/raft control UI. And there is a button in the overriding control UI displaying a horse, which is also a part within this bug report.

Expected: The new control UI should not override within the old boat control UI and should depend by the selected control mode. Also the horse exit button should be only for the horse, not in any raft or boats.

Minecraft world details:

Any command blocks enabled: No

Any texture packs enabled: Yes, but it doesn't affect the UI. (Texture Pack(s): Beta Hider)

Bug affects: UI and UI texture

Bug does: override/overlay

Tested with: Bamboo Raft, Bamboo Raft with Chest, Oak Boat and Oak Boat with Chest.

*Bug is in-investigation by me. I will leave some updates.

Update: Turns out my report has a few duplicates. I also will not need to investigate this anymore because this issue is being solved.