Minecraft version: 1.21 (duh)
Mod list:

crash report: https://pastebin.com/zgpyrSaJ

Bobby mod site: https://modrinth.com/mod/bobby
Bobby source code: https://github.com/Johni0702/bobby/

I've also tried the two other versions of Bobby for 1.21, and none worked.

I know the error is technically on Bobby's side (as seen from the crash report), but still, thought i should post it here, since this is a dev build, and hopefully you might be able to do something about it too :)

Source code crash walkthrough:
Bobby.onInitializeClient(Bobby.java:83): here
Bobby$MaxRenderDistanceConfigHandler.(Bobby.java:240): here
Bobby$MaxRenderDistanceConfigHandler.update(Bobby.java:248): here
Bobby$MaxRenderDistanceConfigHandler.setMaxRenderDistance(Bobby.java:258): here

well when i did the walkthrough, i was so damn confused, like, it crashes on this line:
SimpleOption<Integer> viewDistance = client.options.getViewDistance();
client and options are both non null, thats fine, its the .getViewDistance() that causes the crash.
but i mean, what the hell does NBTEditor have to do with render distances, why would Bobby crash because NBTEditor is installed xD

A while ago in the Discord, someone mentioned that Bobby requires an older version of the Fabric API - when you installed NBT Editor, did you also have to update Fabric API? If so, try it without NBT Editor
Looking at the error, it seems like the options field is null due how Fabric calls mod entrypoints within MinecraftClient's constructor - there shouldn't be anything in my code that messes with the initialization of options or the calling of mod entrypoints

The game starts up fine with just bobby+fabric api and with nbteditor+fabric api, its the combination of all three that doesnt work.
I mean I've since fixed my problem by modifying Bobby's source code to get around the error, so i don't really need you to fix this, but other people might be experiencing this so...

I have this issue too, yeah... I'd love to be able to use both at the same time..

Image where the game starts up as normal^, but when I remove '.disabled' from the file extension of NBT Editor, the game crashes on startup:
Crash report: https://pastebin.com/CLWSKuRN