Sorry, I'm not familiar at all with Safari. But on Firefox I logged out and logged back in, there's a box to check that says "Remember Me", as long as that's checked and Firefox has saved my username/pw I just get logged right in.
Just because you bought a Macbook, there's no reason to convert to Safari. Personally, I've continued to use the Chrome browser on all my Macs. Firefox and others will work just fine as well.
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Bob C
2002 Itasca Suncruiser 35U
Workhorse Chassis
I use Firefox on my MacBookPro. Just a personal preference.
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Wayne MSGT USMC (Ret) & Earlene (CinCHouse)
2015 Winnebago Tour 42QD - 2020 Lincoln Nautilus Reserve (TOAD)
(RVM-14) It is what it is, and then it is what you make of it.