Painting holds more space than it is supposed to do

"2 men karate" painting holds 2 extra blocks. It is 4 blocks wide and 2 blocks high, which means that those blocks are extra. Trying to place that painting on a 4 b. wide and 2 b. high wall will not work (that painting won't place). Placing it on a 5 b. wide wall will work but when removing those blocks, painting will break (see the screenshots).