OS' native tab design?

[gazecube]

I'm trying to emulate Firefox 1.x but the tabs on those ancient releases use the OS' native tab design. I feel like this would be good for users trying to get the look of those even earlier browsers.

[Aris-t2]

Even, if this would work (like it did in the past), you would get different results requiring individual tweaking on every OS.

.tabbrowser-tab {
  appearance: auto !important;
  -moz-default-appearance: tab !important;
}

In the past this did restore OS default tabs:

.tabbrowser-tab {
  -moz-appearance: tab !important;
}

[gazecube]

The top CSS gets it kinda close.. The new tab design shows over the system-styled tabs, and the tabs are quite thick, but if I can make em' smaller and remove the weird middle-part going on, this might actually look good.

Holy crap they look sweet! :D https://imgur.com/a/vgvY49B

[Aris-t2]

Looks good.