Everything works fine alone. A friend of mine joins the game, everything works fine. My friend leaves, I research the upgrade planer. (Not using it yet, as I don't have robots yet. I'm taking it slow, also rso is kinda hindering progress with very rare deposits

Another friend of mine joins and suddenly I can not save anymore with the following error message:
"Notice: Error while running on_Load: GUI write access while saving game is not allowed.The save event shouldn't abused to change game state in any way."
Apart from that that error message makes grammatically no sense whatsoever there was also no save created. The other player is already registered in that game, I can save before my friend joins, but not afterwards. It's his first time on the map. I think i didn't have the stuff researched when my other friend was last on the map, i will try to invite him again when he has some time and try saving with him there, and then if it doesn't work, with him left after coming.
Also why is there a on_load call when the map is saving? again that makes no sense, except there is some kind of loop in the on load function that is still running till the game saving occurs, would be very weird, i'd say on load is for initializing, not for providing continuous functionality.
Actually first happened with module inserter, but that uses the same GUI, I think. Not loading that mod would then pop up this error.
I'm writing the report here because you're the author of the GUI (I think?)
Please fix if possible