Attach notes to combinators, entities... almost everything
+ Adds signposts.
All notes are saved when you export a blueprint as a string (but you need the mod to read them).
After adding this mod : https://mods.factorio.com/mod/AttilaSignalsMod
I get the following which implicates 'AttachNotes'. Disabling AttachNotes things seem to work fine,
120.884 Error ModManager.cpp:1294: Error while loading item prototype "firearm-magazine" (item): Prototype "firearm-magazine" registered twice
Modifications: Attach Notes
I don't see a double registration if I disable Attach Notes.
This also seems to cause an issue in AmatorPhasmas Coal & Steam mod : https://mods.factorio.com/mod/apm_recycling/discussion/5cf2f5657bc50c000dab62c2
Fixed in version 0.3.1. Thanks for the report :)