"Failed to read accessWidener file" error in fabric loader when launching

Hello!
I'm a total noob when it comes to mods and reading error messages, so I hope any of y'all could help me understand this one, and maybe help me fix it.
I dont know if any of my other mods are dependent on this one, so I dont dare just remove it yet. I have it installed because it was on a list of mods I got sent from a friend. It's for a server they're hosting, they're away and cannot help me.
Any tips and tricks are very welcome!

After clicking the play button in the minecraft launcher, the fabric loader box pops up with an error message. I've had that happen before when I've got the wrong version or am missing a support mod, etc, but this error message is eew and unfamiliar to me:

---the start of the error message---

Uncaught exception in thread "main"
java.lang.RuntimeException: Failed to read accessWidener file from mod yet_another_config_lib_v3
at net.fabricmc.loader.impl.FabricLoaderImpl.loadAccessWideners(FabricLoaderImpl.java:534)
at net.fabricmc.loader.impl.launch.knot.Knot.init(Knot.java:145)
at net.fabricmc.loader.impl.launch.knot.Knot.launch(Knot.java:66)
at net.fabricmc.loader.impl.launch.knot.KnotClient.main(KnotClient.java:23)
Caused by: net.fabricmc.loader.impl.lib.accesswidener.AccessWidenerFormatException: line 1: Invalid access widener file header. Expected: 'accessWidener '
at net.fabricmc.loader.impl.lib.accesswidener.AccessWidenerReader.readHeader(AccessWidenerReader.java:158)
at net.fabricmc.loader.impl.lib.accesswidener.AccessWidenerReader.read(AccessWidenerReader.java:78)
at net.fabricmc.loader.impl.FabricLoaderImpl.loadAccessWideners(FabricLoaderImpl.java:532)
... 3 more

---the end of the error message---

Start with the reported stack trace, especially FabricLoaderImpl.loadAccessWideners and AccessWidenerReader.readHeader, then inspect the installed yet_another_config_lib_v3 artifact. Confirm which file is being read and whether its first line matches the access widener header expected by the reported Fabric Loader version; done means documenting a reproducible cause and the affected versions.