Setting dimensions in animation editor that exceed image size leads to breakage

[swordmaster2k]

At animation editor, setting tile width to more than 128 and selecting a tile somehow makes the option to change the image disappear. Also, when saving said animation, it cannot be opened again (although it can still be used ingame and it shows no problem at all). Seems like this problem was already present at v1.5 as i cant seem to open as well the animation file saved this way. @swordmaster
Edit: ah well scratch that. It occurs when the chosen dimensions in the animation editor exceed the image's size