Comment 5 for bug 1586493

There's UI to change the aspect ratio limit too in 1.3.0. Requires docking enabled and extend setting checked (default).

Depending on the active layout, either long press the move button or long press Return and select the move button to show the touch handles. The single handle on the right changes the aspect ratio. Pull it all the way to the right to have it snap to the screen edge and disable the aspect ratio limit, i.e. always stretch from side to side.