Blender is creating dozens/hundreds of SimpleWorlds as I edit

So I just updated a base material for myself so I’ve been applying it to all of my models, but as I’ve been editing them I’ve noticed that Blender has been creating dozens of worlds in my file, all called SimpleWorld, and are just a basic Background node attached to the output. Sometimes it can have created hundreds of them after a while of editing.

Screenshot 2026-03-08 141351
Screenshot 2026-03-08 141457

Thankfully I can clear them out by purging unused data, but it would obviously better if they just weren’t being created at all. As far as I can tell it seems to create them when I’m just editing the material, but its hard to tell since it creates so many. I tried quickly editing a material to see if it made any, but it didn’t. So, I’m not sure what’s going on.

I don’t know if it would even matter, but here’s my new material setup and the world shader I already use. The material is in a node group, but outside of it is just color nodes. The program does freeze frequently when I make bigger edits to the material, but it’s frozen lots of times before and it hasn’t created random worlds in the file, so I’m not sure why it’s happening now.


I’m in 5.0, but the problem didn’t start when I updated, it seemed to only be happening once I made that new material and started adding it to everything. I’m not sure why editing a material would cause a bunch of worlds to be created though.

Thanks for any ideas

AFAIK blender does not name anything simple (or starworld)… so… do you use some addon/extensions ??

Well it seems like it does, I also found this post having the same issue, and they’re calling it a legitimate bug: https://projects.blender.org/blender/blender/issues/153293

Guess we’ll just have to wait for an update lol

You may have some add-on doing that. Blender itself definitely doesn’t do that on its own. Any chance you have used AI for coding add-ons recently?.. :laughing:

Good finding ! I would probably have burned all my addons before thinking this might comes from blender…

I didn’t tested 5.1 but it seems it’s fixed there, in the meantime I guess we’ll have to keep that preview shader panel closed…

Blender DOES do that on its own, it’s confirmed as a “severe bug” in the linked bug report

OK, it’s a weird one then. since when am I lucky to not experience existing bugs?..

Yes… this is not “Simple…” :stuck_out_tongue_winking_eye: