Capital letters do not work in a structure block

When you try and write a capital letter, either with shift or caps lock, it will not work in the structure name section. However, if you try and type it in any other part of the block it will.

How to reproduce
1: Obtain a structure block by typing /give @s structure_block
2: Place the structure block down on open it by right clicking it
3: Try and type a capital letter. It will not work