I need to duplicate a mask including its animation to invert it and apply it on a movie strip. Is there a possibility to do it? In the dope sheet in mask mode it says "Keyframe pasting is not available..". In recent version it was possible via a number button next the mask name, but this button does not exist in 2.81 any more. thanks daniel
Save your file with a new name (myproject_tmp.blend), then reopen the original file. File/append, select myproject_tmp, Mask, mymask, Append.
You can now delete myproject_tmp.
That's a dirty workaround... The miss of this button is either a bug or a regression in my opinion.