Mask only working on keyframes and not mid-tween

[williamfulwood]

I've got an animation with a series of masks using shape tweens to animate and reveal the content below. All but one of the mask layers is working fine as intended, I can't really tell what the difference is but for some reason the mask that looks fine on the timeline once published just reveals the content at each of the keyframes and not mid-tween as it should. So the content flashes up and then goes away as it plays through.

It seems like a bug to me, I can convert the animation to frame-by-frame but I'd rather not as that's real pain to work with later.

Wondering if anyone has seen the same, using version 21.0.3

[williamfulwood · Accepted solution]

Update I just re-drew the mask with a slightly different method, keep position and change transform point/scale rather than moving the position of the rectangle primitive at all (although I'm fairly sure this will export as roughly the same thing) and its working.