Mask: From File loses track of file upon reopening

System: macOS 11.2.2

Shotcut version: 21.03.21

I added a Mask: From File filter to a clip, then selected “custom file” for the file and pointed it at a png of a gradient. I then keyframed the threshold of the mask in order to create a drop-down effect.

However, after I saved and then reopened the project, the mask filter doesn’t seem to be doing anything.

Despite the fact that the filter still claims to be pointing to the file.

If I then go File → Custom and reselect the file, it works as expected again. (at least until I reopen the project.)

Here is the example project in question

mask (4.1 KB)

This is a known problem, fixed in the next release. See here: