Marking tiles in map editor will sometimes instantly clone stamp them elsewhere

[rversteegen]

Foxley wrote (on 2018/08/26, using a nightly):

one thing that's becoming the bane of my existence with laying maptiles is that after pressing space/enter after selecting an area with Mark, it will often instantly clone stamp onto an area you didn't even select

I thought someone else mentioned having the same problem, but can't find any reference to that now. Also it might be the cause of or related another bug which I'm filing now (#1130).

(Aside, Foxley also complained about walls being erased when using mark+clone but when I asked whether it was because having Tile Merging (Ctrl-M) off while using the Clone tool will overwrite the existing walls, he replied "Oh, it's probably because I prefer tile merging off")

Also, in #738 I found the following (from 2010):

Also, Dark Blubber reported "Sometimes when I do a lot of tilemap work and then push Enter to show the full tileset and pick a new tile, one random tile from the tileset is duplicated in the wrong place."

Not clear whether that means duplicated on the map or in the tileset, but note that the tileset is also displayed using a TileMap.