That's a killer feature, thanks a ton!* ADDED: Press 'X' or 'Y' to flip arrows, corner tiles and directed edge styles (one-way doors, torches, etc.).
* ADDED: Flip support for ramps, stairs, ladders, teleports, entrance/exit and treasure chests.
With it implemented, a lot of edges now can be removed from the editor. There's no point in having two of everything there — two buttons, two torches, two niches, two one-way wall, etc — when it suffices to keep only one that can be rotated as needed.
I think this will make the Edges panel much less cluttered and more readable.