Safari Tabs disappear from Tab Group

[ApAx]

I have a tab group set up in Safari on macOS 15.6. The group contains about 16 tabs. I can confirm that I quit Safari and reopen, and the tabs are still there. But each morning when I start my day, the tabs get removed and the group has no tabs in it, and I have to manually browse to the sites and add all the tabs back.

Is there a known issue, or a setting I am missing to "keep tabs?" These are frequently opened all together, and not a one-time thing, so I don't want it to function like a read later list that clears itself out.

 

[IJustWannaTalk]

I lost almost all of mine. Didn't even know this might be a thing.

 

[nmt1900]

Tab Groups have other problems as well. When I tried to sync Safari data over iCloud from one Mac to other then Tab Groups were either missing or empty.

 

[ohbrilliance]

Tab groups are a mess for me in MacOS 26.0. Opening an existing tab group causes another non-tab-group window to disappear. The top item of the tab group dropdown then has a 'x tabs' item that doesn't correspond to the number of tabs in the window that disappeared. Opening that gives me a set of tabs that had long disappeared (perhaps the previous time I'd tried to open a named tab group?). Closing the named tab group then presents me with a message 'closing x tabs?' or similar, where the number for x doesn't correspond with the number of tabs in the current window.
This all leaves me feeling nervous, especially since I use a non-tab-group window for running tabs that I intend to pay attention to before closing.
I'll see whether this improves with 26.0.1 or the impending 26.1.