Error message following:

26.598 Error ClientMultiplayerManager.cpp:1072: mod-osm-lib was not registered for the following events when the map was saved but has registered them as a result of loading: on_tick (ID 0)
26.598 Error ClientMultiplayerManager.cpp:1072: mod-osm-lib-postprocess was not registered for the following events when the map was saved but has registered them as a result of loading: on_tick (ID 0)
26.598 Error ClientMultiplayerManager.cpp:99: MultiplayerManager failed: "" + multiplayer.script-event-mismatch + "
" + "
mod-osm-lib" + "
mod-osm-lib-postprocess"

May i have the savegame please

Here's savegame: https://www.swisstransfer.com/d/63c7277d-0f10-4a33-9b0b-82b6dca22591

The error is reproduced even on a new save, like this one. The host is fine, but the client gets the following when trying to connect:

Cannot join. The following mod event handlers are not identical between you and the server. This indicates that the following mods are not multiplayer (save/load) safe. (See the log file for more details):

mod-osm-lib
mod-osm-lib-postprocess

duplicate message

FIXED!