… the fiefdoms remain.
There doesn’t seem to be a combination of browser extensions that gives me the combination of features I want, in the experience I want, to have some parity across the multiple browsers I use every day.
The shortlist (this is not all-inclusive) might be:
- Safari’s “merge all windows”
 - Safari’s “arrange tabs by web site” (or alphabetically by title)
 - Chrome’s tab groups (Safari’s groups are closest, But I like the in-tab-bar experience a little better)
 - Syncing of groups across instances/platforms on that browser (Safari does it best, I want the same experience on Chrome, Firefox)
 - Firefox’s containers