Hi! We're playing a multiplayer (two people; me and one other person with me hosting) game and encountering a bug where, when the second person tries to enter the game, they're getting the popup asking them to begin migration, but the "Migrate!" button doesn't respond when clicked. We made sure the migrate setting was unchecked on both of our systems. I tried to have the other person save and load and I join their session, at which point I get the same bug. Let me know if you need additional information.

Are you on the discord by any chance? I'd like to see what's happening if possible.

I have been unable to reproduce this. If you could provide some detailed steps to reproduce and a save file this is happening in, that would help a lot.

I'm on discord, but not on your specific discord server; I'm ChickinSammich on Discord if you want to send me a PM.

Steps to reproduce: I launch the game, host the game, other person launches the game, opens friend list, right clicks on me and tried to join game, downloads map, and then gets the popup. I'm happy to provide a copy of my save, and/or screenshots, and/or try to coordinate testing with you (if I'm not at work).

Can't find you on the Factorio Discord. We can try to coordinate something to test there.

I joined the Factorio Discord server that you linked

I have the same problem here with a friend on a multiplayer server. The Migrate window pops up. Even i make my friend admin, klicking on migrate does not do anything. Please change the migrate window in a way, that you can at least close it.

FYSA - I relayed this info to kryojenik via Discord PMs but here's some info for Schuby and for anyone else lurking:

Okay so we have some interesting new behavior and test results
So I'll refer to myself as "I/me" and the other person I'm testing with as "Player 2"
I did the initial migration of the map to Miniloaders modernized.
When I host, Player 2 gets the "migrate" popup and can't dismiss it
We did a test: We had Player 2 load a pre-migrate save and do the migration himself
As a result, he no longer gets the migrate popup but now I do (on the new test forked map)
So it appears that the symptom is that, in multiplayer, the person who DID NOT do the migration can't dismiss the popup

...and:

We've verified this test in both directions:
One of us checks the box
Loads the pre migrate save
Does the migration
Saves and quits
Unchecks the box
Loads the game fine with no issue
The other person, box unchecked, joins multiplayer via steam and gets the migrate checkbox, and clicking "Migrate" does nothing

...

Incidentally: You can just drag the window to the corner of the screen as a workaround to keep playing in the interim. That's what my other player has been doing.

I've been able to reproduce this. Working on a fix now.