Bug Report Text shows up as rectangles

[hkminegod]

When livestreaming, there is a 50% chance that the text will show up as rectangle, demonstrated below in this youtube video:
https://www.youtube.com/watch?v=O9yA3n1_BQg

No idea how to reproduce, but it happens randomly. Tried to change font, delete and remake, change the text via the textfile, but nothing changes it back from rectangle to normal text.

 

[Light And Magic]

I have seen this plenty of times when editing my scenes, just quitting the application and restarting did help, as well as removing the text line and putting on a new one, so I do know this behavior and never found a real reason why it happened in my scenes.