You can share a Tab Group and collaborate with people who use iCloud. Everyone you collaborate with must be signed in with their Apple ID, have Safari turned on in iCloud settings, and have two-factor authentication turned on.
Share Tab Groups
In Safari, place the pointer over a Tab Group in the sidebar
Click Share Tab Group - if the sidebar isn’t shown, click the Sidebar button in the toolbar
Click Messages, then enter the person or group you want to share with
You get activity updates in the Messages conversation when someone makes changes in the shared Tab Group. Click an update to go to the shared Tab Group.