Now imagine they're powered by a docking station, you go into suspend, put the laptop out of the docking station, wake it up and - tadaa! This bug dissappeared but still occurs slightly diffrent for other people. Three monitors itself aren't more edgecase than 2. How long are you using this setup?

Besides screenlockers, having 2 screens with diffrent resolutions is way worse in KDE than in GNOME. (On X11)