I have been playing on 2.0.77 until now, and after upgrading Factorio to 2.1 and updating my mods, trying to load my save results in this error.
"The mod Hextorio - Build in hexagons (1.9.9) caused a non-recoverable error.
Please report this error to the mod author.
Error while running event hextorio::on_configuration_changed
hextorio/api/migrations.lua:187: attempt to concatenate field '?' (a nil value)
stack traceback:
hextorio/api/migrations.lua:187: in function 'on_mod_updated'
hextorio/control.lua:546: in function <hextorio/control.lua:543>"
Other mods are Rate Calculator and Disco Science.
