On laptops with a NVIDIA dGPU and a AMD Renoir iGPU, and an external monitor plugged to the dGPU, without MR 3304 the external monitor is simply unusable – even typing shows noticeable lagging.
The MR has been created 3 months ago, and has successfully been tested by a couple of users, with very positive results; it literally makes external monitors usable again. Me and others are currently depending on a dedicated COPR repo to install patched mutter versions on Fedora 39, but it would be great to see this finally merged to main 
(there is an issue with mutter 46, but there is already a fix for that)
I understand this is probably not the best/proper way to raise awareness to this issue, but since MR 3304 seems to be in a limbo, I hope this will bring the necessary attention to it, and hopefully speed things up a bit 