After buying a Woodland Mansion map from a cartographer, the mansion maps are completely blank. They have no tracking dot and there is no terrain.

I did recently delete the map NBT files in /saves/WORLD/data/, because I had a lot of useless maps and decided to delete them, as well as idcounts.dat, so I could start back from map id 0.

Regular Maps when created, after the map reset I did, still work fine.

Other worlds are fine, just the current one.

UPDATE: Also applies to Ocean Monument Maps

UPDATE: Relaunched in Vanilla Launcher, same map.