Fading an png image placed on top of a video leaves black shadow until fully faded

[shotcut]

I just added this to the FAQ

Opacity not working

In the fade out filter did you tick the box saying “Adjust opacity instead of fade with black”?

And before you ask why this is not the default:

Fade In and Fade Out filters. Adjust opacity instead of fade with black

This will not work with the primary use case of fading on V1 because V1 is not blended with the hidden black background as a performance optimization. If it did do blending, then it completely makes sense to remove the option and simply fade the opacity. However, the video processing performance is already an issue for most people in general such that I have not changed this model. If the performance improves significantly in the future then I will change this.