Layermask-icons changed to a smaller size

[RoyCoumans]

Somehow by some keystroke I didn't notice the size and icon of the layermask icons changed to a smaller size and the symbol was changed from black or white to the default mask-icon. How can I change it back to the default setting? See attachment. 

[Conrad C · Accepted solution]

I don’t know what the keyboard shortcut is, but are you able to set it back by changing the option below?

[RoyCoumans]

That's it! Thanks a lot!