Attempting to load the (invalid) data pack zip file attached to MC-124368, my world took more than one minute to load while on the "loading world" screen:
18:43:51 cmj Server thread info Changing view distance to 16, from 10
18:45:07 tn Server thread info redstonehelper[local:E:b6afc3da] logged in with entity id 7 at (1179.9282906488722, 56.0, -1371.5211635538456)I've attached a forced crash report for system info.
Can you reproduce with a valid zip file, or does it only affect invalid ones? If it's only invalid ones I'm going to call this "won't fix".