I'm currently attempting to migrate a Razi Protocol mod from the original Factorissimo 3 to this version, but that ambient music bug is preventing my game from loading. If I understand this mod's page and changelog correctly, I'm meant to load the original mod and this one concurrently to successfully perform the migration, right? Or can I leave the original mod unloaded? I've been told that Castra Prime is the planet that's got a lack of ambient music.

Failed to load mods: core/lualib/dataloader.lua:23: Invalid array of prototypes:

{}
stack traceback:
[C]: in function 'error'
core/lualib/dataloader.lua:23: in function 'extend'
...ctorissimo-2-notnotmelon__/prototypes/space-location.lua:134: in function 'add_music'
...ctorissimo-2-notnotmelon__/prototypes/space-location.lua:172: in main chunk
[C]: in function 'require'
factorissimo-2-notnotmelon/data-updates.lua:1: in main chunk

Yes, both mods have to be enabled together for the migration. Factorissimo Gadgetroch stays inert, copies the factories across, and then tells you on screen when it's safe to remove the original. Don't leave the original unloaded: Factorio would delete every factory from the save before anything could be migrated.

But look at the path in"factorissimo-2-notnotmelon/prototypes/space-location.lua:134". The crash is in the original Factorissimo 3, not in this mod. It has the same bug with planets that have no amixed it here in 3.19.3,but the original still has it. Make sure you're on 3.19.3 of this mod, then
patch the original locaand you only need ituntil the migration is done:

1. Unzip factorissimo-2-notnotmelon_x.y.z.zip in your mods folder (keep the extracted folder name exactly as it is, then move the zip out of the folder).
2. Open prototypes/space-location.lua and go to line 134, inside add_music.
   It reads:
   data:extend(new_
   Replace it with:
   if next(new_musics) then data:extend(new_musics) end
3. Load the save with both mods enabled, let the migration run, and remove the original when the p

Please don't disable the Castra mod to get around it either: the planet and everything on it would

Thanks, that edit worked!

Glad it worked, thanks for reporting back!

For anyone else hitting this: 3.19.4 is now out and handles it on this side, so you no longer need to edit the original. Update Factorissimo Gadgetroch to 3.19.4, load the save with both mods enabled, let the migration finish, then remove the original once the on-screen message says it's safe.

If you already patched the original by hand, there's nothing to undo: the edit goes away when you remove that mod.