Mirrors/Flips a blueprint in hand. WARNING: if you are using factorio 1.0 or factorio >= 0.18.37 then you must use the workaround below: - Grab the blueprint from the new blueprint interface - Drop it in the inventory to make a copy. (there is a row of buttons across the top one of has the letter C on it that is the copy button fot the print that is highlighted) - Grab that copy - The flip buttons work on this copy. This issue is not fixable for now, due to Factorio API limitation.
Mods introducing new content into the game.
