Left-Click on a tile in the Map Window should show information about that tile in the Messages window ("cobblestone", "sign", etc). However, it seems the info/messages getting sent are not correct for the tile clicked on. This does not seem to be affected by "mapscale" either, as we seem to have the same issue if mapscale is set to 100 or 150 or 200.
Fixed in b7831e664b, thanks.