The Safari switch
is greyed out.

The in-app page showing the three Settings steps to turn on the Safari extension
01

The normal route: Settings, Apps, Safari, Extensions, Eclipsis, Allow.

The Truly lock this down guide with the Screen Time web content step
02

On a kid's phone the switch is frozen by Screen Time's web filter.

Get Eclipsis. Free on the App Store. The slowdown and Parent Mode are Eclipsis Pro.

Get the iPhone app

Questions

So how do I switch it on?
On the parent's phone: Settings, Screen Time, the child's name, Content & Privacy Restrictions, App Store, Media, Web, & Games, Web Content, choose Unrestricted Access. Switch Eclipsis on in the child's Safari settings. Then set Web Content back to Limit Adult Websites.
Does it stay on?
Yes. The filter only stops changes. With it back on, the child cannot switch Eclipsis off either, which is the point.
It is my own phone and still greyed out.
Check Settings, Screen Time, Content & Privacy Restrictions, Web Content on your own phone. Any setting other than Unrestricted Access freezes the switches.

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