Is it possible to add a check for the mod if its on clientside or serverside?

https://github.com/MattCzyr/Notes/blob/master/src/main/java/com/chaosthedude/notes/Notes.java#L16

@Mod(modid = Notes.MODID, name = Notes.NAME, version = Notes.VERSION, acceptedMinecraftVersions = "[1.12]", clientSideOnly = true)

The mod explicitly tells it is client side only.

Do you have an error report, or logs to show us?

@Poslovitch While it is set to client-side only here on Github, it is not on Curse. The latest version was uploaded one month before that commit was pushed.