[1.21.1-2.17.3] Creative tab crash

[Gronglegrowth]

For some reason, in my personal modpack, opening the creative inventory will cause a crash and the log appears to blame Essentials adding an erroneous item to its creative tab. This crash doesn't happen with only Essentials, so it's certainly a conflict of some sort but I did not particularly feel like binary searching my modlist at the moment. As a result I cannot give reproduction steps etc.

Here is a log: latest.log

[MrDrProfNo]

A similar issue was reported by discord user Alator, who also posted on the BetterNether_Neoforge repo here: Reijin2312/BetterNether-New-Dawn#20

It looks like the broader issue in both your case and Alator's case is that crossroads (via essentials) tries to grab a book item from Patchouli, which then triggers some hard to understand registry loading under the hood that encounters a bad registry and fails.

So why's the registry bad?

I think in Alator's case, it's the BetterNether error they reported in the above issue.

In your case, the logs vaguely point in the direction of registries being used by Vampirism, but it's unclear if those are actually at fault, or another victim of a separate failure.

Earlier in the log there are frequent failures to read a json file that is malformed, all of which (I'm pretty sure) cite the same failure point:

com.google.gson.JsonParseException: com.google.gson.stream.MalformedJsonException: Use JsonReader.setLenient(true) to accept malformed JSON at line 3 column 20 path $.pack.description

I can't find any indication of which json file this is, unfortunately. Might be worth taking a scan through any that you might have modified yourself.