Help on layer mask

[MrGimp]

(07-01-2018, 12:35 PM)TheFunnySide Wrote: I was only able to reproduce this with a layer that had no alpha channel when i applied the layer mask.
If this is your problem then add an alpha channel to the layer.

Thanks for the suggestion. I do have an alpha channel added, but it doesn't stick. I feel like I should do something like click ok to make it work, but I don't see how to.