Fill container should be a button. Right now there’s a button and keyboard shortcut for hug, but fill is just as if not more important, yet it has neither a shortcut nor a button.
If hug is a button, it also doesn’t make any sense for unclicking it to do nothing. You could easily add functionality to switch between states (either hug/fill or hug/fill/fixed) by pressing the button. Instead, currently you can click it once to hug, and then click again to do nothing.
Please add a fill button or make the hug button more functional!