If you create a custom sovereign with a max-length (33-char) name, the last 3-3.5 characters are truncated in some cases.
For this test case, the sovereign is named: 123456789012345678901234567890123 (note the final "123"):

The last 3 characters ("123") are truncated on:
1. The card shown while creating sovereign (the last 5 visible chars are also wrapped past the title bar):

2. The book shown after the map initially loads:

3.In-game Unit Details (unit History correctly shows all 33 characters):

4. In-game Tooltip (truncates the last 3.5 characters):

The tooltip also shows some weird overlapping (bottom).