Just sharing this tutorial on masking. I thought she did an excellent job of showing how to mask quickly or well, as quickly as possible. I've never been a fan of rotoscoping or masking, so I appreciated seeing the way she does it.
For her use where she's masking out the character to put on an alpha background. You may as well do it in photo editors such as photoshop or on the cheap end photo director. They have content aware fill option where you scribble over the background & it masks out everything but the character. It can literally take seconds per frame instead of the horrifically long time it's taking that girl to do that procedure.