Pause menu buttons show as "lines" only in Minecraft

I’ve been playin Minecraft for Windows 10 for about a year now and I’ve never encountered this issue until now, I’ve also searched forums and discussion websites and I haven’t found any other cases.

I opened one of my saves today and when I tried to access the in-game pause menu (pressing Esc) the buttons were reduced to lines in the middle (see pic). I can’t save or access the game options while playing.

I’m able to access the settings menu before loading any game but I couldn’t find any setting that may have been changed. I even re-set all the settings to default and it didn’t help. Tried rebooting my PC but it didn’t do anything.

I can pause and resume the game with the Esc key but menu still shows the same and I can’t switch worlds without closing Minecraft completely, and since I can’t save before exiting, I have to rely in the auto-save, which makes me loose a few minutes of game between auto-saves. Is there anything I’m missing?

I’m considering re-installing Minecraft to check if that fixes it but I don’t want to lose my worlds.

Thanks in advance for the help