I'll just go ahead and describe various rendering bugs I'm experiencing under Wayland. They do occur without discernable pattern, or none that I could recognize anyway, while browsing even moderately demanding webpages with MiniBrowser from 2.18.1 a) Page loads, then turns gray, the location bar goes empty, refreshing the page sometimes, but rarely helps b) Page loads the visually freezes, navigating back or refreshing does have no visual effect, although moving the mouse over various areas of the frozen page makes it interact with the "actual page" c) Page aturns gray and flickering like in bug 171161 I need to ask for some instructions for what to do to narrow it down. bisect is not an option I'm afraid.
Also, WEBKIT_DISABLE_COMPOSITING_MODE=1 is set in the env, so it might not be related to bug 171161.
I think I found a strong correlation between the following case d) d) Page freezes, location bar goes empty, refreshing always helps and jackd running. Jack crashes (segfaults? Haven't determined yet) while playing (e.g. mpd). Without jack, the frequency of case d) reduces notably (perhaps to 0)