Safari and Tabs

I have run into a strange Safari problem. I have 37 tabs set up to appear when I open Safari. These are the web sites I want to review each morning (TidBits and Tidbits Talk are two of the tabs). Given my hardware (MBP16 Pro Max and Mac Studio Pro Max) there is no noticeable delay using this number of tabs. But, occasionally, when I open Safari, my 37 tabs are padded on the right with another set of these 37 tabs - and occasionally it gets worse - I have gotten up to 150 tabs (just repeats of the original tab set). There is a command to close tabs “to the right” which I use - but this keeps happening. This behavior - which I had seen before, a while ago - started again when I set up the new Mac Studio and “decommissioned” the iMac Pro for trade in. I haven’t been able to figure out why this occurs sometimes but not always. Anyone run into this behavior and have any suggestions to stop it? Seems these days with Apple software “strange things happen” and I never know why.

I assume you have this configured my settings the “New windows open with” option set to “Tabs for…” one of your bookmark folders.

Should I also assume that you have “Safari opens with” set to “All windows from last session”?

If so, then you may be seeing an interaction between the two. Safari starts, creates tabs from the previous session (your 37 tabs), and then because it’s a new window, opens the 37 as it would for a new window.

I tried this on my Big Sur system, and it seems smarter than that. I didn’t get duplicates, but you pointed out that it started after putting a new Mac in service. Are you possibly also sharing your tabs between your computers over iCloud? It may be that each Mac doesn’t recognize the others’ 37 tabs as copies of its own. If so, turning off one of these options (reload previous session, iCloud tab syncing or auto-opening a folder for new windows) should be enough to break the cycle.

FWIW, I also have a bookmark folder full of tabs I like to open at once. But I don’t configure my browser to auto-open them, because I usually quit my browser when I’m not actively using it and I don’t always want to open them all. I have my browser configured to open all windows and tabs with a blank page. When I want to open the folder of bookmarks into tabs, I right-click the bookmark folder and select “Open in new tabs”) .

(Actually, I normally use Firefox, but it has the same capability, but with a different gesture.)

Thanks for the response. Your assumptions are correct. I tried turning off the Safari iCloud sync and that didn’t help. If this continues, I may just covert to your mode - opening with the DuckDuckGo search page and then opening the tabs bookmark when I want it.

There is just something weird happening. Sometimes I open Safari and get my 37 tabs (only); the next time I open Safari I get two copies of the 37 tabs. I can’t figure out what I am doing differently to get the different behavior.