I think that downsizing the scene to like 8x8 pixels (so basically taking the average color of multiple sections of the scene) would mostly work. In order to be undetected, the ad would have to match (at least be close to) the average color of each section, which would be difficult in my opinion: you would need to alter each ad for each video timestamp individually.
I had to use X11 before because using Wayland introduced many bugs (like freezing of some popups and the bottom tray). With updating to Fedora 40, Wayland became the default, which, again, caused many bugs mostly in electron apps (discord) a I wasn’t able to play a minecraft modpack because the whole screen was flickering. But after installing the nvidia driver 555 (still in beta at that time), everythings runs smoothly.