If you enjoy watching movies & Youtube on Edge browser, this is a cool extension - Turn off the Lights, by Stefan VD. It's a handy little extension that dims the background around the video window, cutting out distractions. Here's what it looks like:
I've been using it for about 2 weeks and have encountered only one issue - it popped out and stopped working until I shut Edge down and restarted it. Other than the one instance, I've had no other problems. Get it the usual way, Microsoft Store ->Extensions->Turn off the Lights. Once installed, it sits on the screen's toolbar within easy clicking distance.
Download the extension here: Turn off the lights
The image still is from Professor Quatermass and the Pit - BBC sci fi serial from the 1950s. One of the best sci fi series ever made. Go watch it ... no .. go .. now... Watch it. Where else can you see extinct giant Martian grasshoppers destroying humanity?