I think the latest miniloader change re-introduced an old bug. When used with the warehouse mod, snapping a miniloader in place causes a desync.

The problem does not occur if you disable "snap miniloaders".

The problem code might be the use of a local to save the use_snapping variable.

local old_snapping = use_snapping
use_snapping = false
event.on_next_tick(function()
...

Can you give more detailed reproduction steps? What do you mean by snapping a Miniloader “in place?” Does the Warehouse mod need to be present for the bug to surface?

For us it would desync most if not all of the online players anytime someone manually placed a miniloader or caused it to change direction by placing belts next to it. It would also desync sometimes if a player ghost-placed a miniloader directly, but it would NOT desync if the miniloader was placed by copy/paste, cut, or upgraded by upgrade planner.

Later, it caused an issue on attempts to log in. (Paraphrased)"Cannot Join. the following event handlers are not identical between you and the server: Miniloaders. This implies that the mod is not multiplayer safe (load/save)."

I have a possible fix now available in v1.12.3, but I can't promise it works since I've not been able to reproduce the desync on my test server with 2 players.

This seems to be fixed now. I haven't noticed any more desyncs since updating.

EDIT: Please ignore. Got a desync while attaching a belt to an undergound belt.

Hello,

I still have this issue when using Linux version of Factorio. Today we (2 players) got desync messages multiple time. It happened when we were attaching a red belt to a loader which is directing down.

Using Factorio 1.0.0 / Miniloader 1.12.3 / Linux Headless Server 1.0.0

Using Factorio on Windows didn't show this issue after updating to 1.12.3. Before id did.