After yesterday’s Arch update it looks as if Slow launch for (some) GTK apps #5732 reappeared. First launch of e.g. mousepad, thunderbird, nwggrid takes ages. Having launched one of above once, I no longer have to wait while launching any GTK app.
First spotted on ArchLabs / River, also happens to me on Arch / sway on my both laptops. Has any wlroots user here (well, probably @dimaom and nobody else) experienced the same problem?