Change colour of Canvas around Viewer windows

Hello
To help identify video blanking issues on source material and comps, adding the ability to change the colour of the cavas around the video player would be more than useful.
Below explains the issue.
viewtopic.php?f=21&t=184329
Thanks

Below is a link that explains how to change the timeline background. I cannot find a similar option in fusion, which only offers the checker board (which is a good start).

viewtopic.php?f=14&t=193099&p=1092642#p1092642

I use the Title Safe overlay to show the edges with a fine line. I find it better than waiting for BMD to add this feature.

I use the Title Safe overlay to show the edges with a fine line. I find it better than waiting for BMD to add this feature.

Blackmagic already added the feature.