This issue has already been posted about before, (at MCPE-110109) but that post did not go into detail about the issue. The issue occurs in the character creator menu when the player has a cape equipped and is trying to equip an item onto their character. 
New video.mp4
When the text appears, your characters cape will be shifted up or down to the location it would be on a medium sized character.
Very Small:

Small:

Medium:

Tall:

The text does not disappear until roughly 5-10 seconds after you close the character creator menu.