Here on Fedora 28 I am testing out the Firefox on Wayland version, which comes shipped through the usual repos.
STR:
What happens: It focuses/jumps to the window behind it (i guess). In my case this was Atom.
What should happen: Just let me screenrecord Firefox.
This does not happen with the "usual" Firefox (xwayland).
Screenrecording itself BTW happens – if you don't click into the area.
Peek from flathub
Firefox 60.0.1-5.fc28
GNOME
BTW this may be similar to https://github.com/phw/peek/issues/306.
Actually I could reproduce it with Nautilus, so maybe it is more related to Wayland than to Firefox. Every time the nautilus window get's unfocused, I clicked on the Peek screen recording area (the "hole"):

I'm having the same issue with Ubuntu 18.04 and Firefox. The window focus is not very intuitive.
Same issue here since i've updated to Ubuntu 18.04.. Can't click through the recording window.
Actually I just noticed it is even worth: The window is actually also intercepting keystrokes! 😲
Any reaction by @phw here? This is a long-standing issue, and made the Peek application totally useless since my bug report. In the past (before that report), it worked flawlessly.
BTW, @Andrew-Wichmann and @WilcoM, feel free to upvote the top comment in this issue to show you are also affected.
Haven't used Peek in awhile but I have a use case for it again now. I'd really like to see this fixed
In Peek v1.3.1 it gets better indeed:
Same thing for me on Fedora 31, using Wayland.
just upgrade from Fedora 30 to 31 then 32
Same trouble with Firefox
Works fine on Chrome
peek package is the one from Fedora repo
version 1.5.0
I have this problem with Peek 1.5.1-37-g70cfebd. Specifically, the program behind Peek doesn't accept clicks, and Peek gains focus instead. I'm using cinnamon/muffin on Debian.
Most helpful comment
In Peek v1.3.1 it gets better indeed: