Safari is too good in this regard, it deletes first party cookies after 7 days, so any site you haven't used in a week it acts like it's never seen you before and is completely signed out.
As far as I know, you can't change this setting.
As far as I know, you can't change this setting.
Technically, all script-writable storage.
> you can't change this setting.
Settings, Feature Flags, Disable Removal of Non-Cookie Data After 7 Days of No User Interaction
Edit: it resets that setting after Safari updates apparently.
If you set it in the global defaults, then Safari won't touch it.