I agree. In Opera One, when I hover over the non-active tab to the left of the active tab, it looks like the active tab is slightly on top of the other tab. They're way too close. They don't look separated and it looks pretty bad. It's probably by design, but I consider it a bug with the way they look now.
I totally agreed this situation, I can't understand why Opera doesn't came this feature to browser. because of this situation for PWA apps, my second browser Chrome.