Looking for a tilemap editor I used last year with a really simple autotile system

I don't know if I'm going crazy, but I swear I used a tilemap editor/program last year that had a really easy autotile system. As far as I remember, you could just place red and blue symbols/markers on the tiles to define things like corners, edges, connections, etc. It was incredibly simple. At first, I thought it was Tiled, but either I can't find that feature anymore or it wasn't Tiled at all. Does anyone know what program I'm talking about? Please help 😭