Thanks!
What permission exactly does trouble you?
I guess the tab permission is a bit unusual.
However, with the Manifest V3, the extension couldn't make any outside calls anyway without explicit permission to do so (and this isn't the case).
The reason for the tab permission is not just to index them, but to also to merge bookmarks and history with open tabs. If you go to a bookmark, you've already opened it will just switch to the tab.