Please don't do this, Mozilla. I have a lot of open tabs on my 1920 x 1080 monitor, and switching from compact density to default (I just tested this) reduced

Please don't do this, Mozilla. I have a lot of open tabs on my 1920 x 1080 monitor, and switching from compact density to default (I just tested this) reduced the amount of visible text on each tab such that I couldn't identify what most of the tabs contained. In other words, if you have a lot of tabs open at once, the reduction in usability is significant.