When the option "return to last active tab when closing current tab" is open,
if the current tab is the only tab and you close it, even if you were just on a pinned tab, it does not return to that tab.
If I was just on a pinned tab and close my current tab, it should return to the last active tab, even if that tab is pinned. This behavior is what occurs when other tabs are open, but not if the one you are closing is the only open tab.
Version 0.99.135.0.1-beta (WebKit 622.1.15.19.2), macOS 15.6 Beta
Sequoia (15)