Comment by malshe
9 hours ago
This sounds more like problem of HP’s dock than a Mac. Just because they said it is officially compatible with Mac doesn’t mean it is. Also, compatible with which Mac- Intel or M series? I use three different docks on two Mac Mini (M4 Pro) and they all worked out of the box. I did my research before buying them by watching YouTube reviews.
So Mac doesn't support DisplayPort MST like everyone else does (Windows and Linux have supported this STANDARD for years), because they are assholes and don't care about their users, and the fact that multi monitor support is different between Intel Macs, certain M1s (cannot use more than one external monitor at all!), and the rest of the Apple Silicon lineup (other M1s, M2+) is insane.
I eventually got it working on this Intel Mac by using one HDMI and one specific DisplayPort output on the dock so it wouldn't try to multistream it internally in the dock or whatever (can't remember what exactly it was doing). It might have involved an HDMI to DP converter. I honestly tried to purge my memory of it once I got it working.
Note that all setups worked fine with Linux without modifications. Would have likely worked fine on Windows, too, since it supports MST. Only one specific setup worked with Mac.
So no, it's not a problem of the dock, it's a problem with Apple refusing to support a standard so they can make people buy the expensive $400 docks they hawk in Apple stores. Or because they are lazy and think because they don't care, their users shouldn't either.
You will find many people complaining about Mac's multi monitor support (or lack thereof) online. They are choosing to ignore user feedback.