This is especially obvious for books where all the text will have color codes after dumping and loading them from the database. In order to be able to still compare to them we will load the item the item and then dump it again if it doesn't match the original one.
For some reason items might corrupt in the encoding and decoding process leading to invalid YAML strings. There's also another issue of the server not being able to load certain old itemstacks. (seems to be especially an issue with old entity types)
Phoenix616
Phoenix616
L4BORG
Andrzej Pomirski
Acrobot