In the attached photo, you can see that Orion reports "4 tabs"; but only one of these appears in the Open Tabs list. I couldn't find those open tabs anywhere and there were no other windows open at the time. After quitting and restarting Orion, all four tabs then appeared in the Open Tabs list.
I don't know the steps to reproduce this, unfortunately.
Relatedly, tabs can sometimes not be closed within the sidebar. Either no "x" appears, or it does but clicking on it does nothing. This was the case with the single tab that was open in the screenshot.
Orion Version 0.99.125-beta (WebKit 616.1.22), Mac OS Ventura 13.5.2 (22G91); 2021 M1 Macbook Pro:
Image/Video:
