Vlad
If what exactly was in the middle?
Sure heres a sketch of mininum size:

The whole idea is that the whatever space there is to utilise on the right side of the adress bar is used for tabs.
meaning you can still add whatever buttons or extentions icons you want.
But in this case of standard layout, within the space that is avalible:

The tab behavior is the exact same as in none compact mode. meaning tabs scale expand and get compressed the same as the user is used to in none compact. making it IMO super intuative. So if you want to imagine how somethng specific would look. you can just look at none compact.
Another reason why i prefer this aproach over the previous suggested or Safaris method is. that since you are on the same horionzontal line, every inch counts. and this way there are no "dead" space between the tabs:

Regarding Safaris coloring and UI merge. i think its a seperate issue and dont think it actually belongs in the same issue as this.
Since it could also be implemented in none compact mode and doesnt change any functionality, its a purely aesthetic thing. meaning you could like Safaris coloring thing without liking there compact tabs, and other way around
But sure i can try to make one. they are a bit harder to make a sketch of tho