This must by far be the most useless change ever!!
I makes my tabs go "micro" sized because i use the whole tab bar when surfing. Not a nice surprise.
And i have found no way to change it sitting on Ubuntu 18 and Opera 55.
And the fact that the HTML% needs to be redone every time there is an upgrade to the browser. As of this update i cant even play games on FB .
I need ti switch browser if this doesn't go away in a hurry.