The mod Factory grapher (1.0.1) caused a non-recoverable error.
Please report this error to the mod author.
Error while running event factory_graph::on_gui_click (ID 1)
factory_graph/scripts/product_panel.lua:262: attempt to compare string with nil
stack traceback:
factory_graph/scripts/product_panel.lua:262: in function <factory_graph/scripts/product_panel.lua:262>
[C]: in function 'sort'
factory_graph/scripts/product_panel.lua:262: in function 'create_product_table'
factory_graph/scripts/product_panel.lua:304: in function 'create_product_tables'
factory_graph/scripts/product_panel.lua:117: in function 'create'
factory_graph/scripts/command.lua:173: in function 'handler'
factory_graph/scripts/tools.lua:430: in function 'previous'
factory_graph/scripts/tools.lua:280: in function <factory_graph/scripts/tools.lua:279>
