Addon windows in the Overflow menu are limited or fixed in size and therefore some addon functions are inaccessible or hard to use. Usually I would just middle-click to scroll sideways but with some addons this is not possible (eg. LastPass only shows the "Upgrade to Premium" part and nothing else if it is in the Overflow menu). I love the minimalist black&white look of my current Firefox setup so having the red LastPass icon outside of the Overflow menu would ruin that. Other addons just look bad with all that extra white space, like Windscribe (which should have a very small Addon window).

Is there some way to change the size of the addon window or report this as a bug to have it behave like addons should?