Extensions for sharing with others. Checkbox missing for AirDrop, Mail or Messages.

However, when I get to the field that enables me to allow extensions for sharing there does not seem to be any option for selecting AirDrop, Mail, or Messages, even though they are listed.

The checkbox is for enabling and disabling, if possible. It is not possible to disable those; i.e., they are always On.

What are you trying to share and from what app?

I'm well out of Ventura, but the way the sharing extensions work hasn't changed.

Running the Newer Version of Ventura 13.3.1

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From Finder I can Share

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I have the same problem. Would expand on the details but OP nailed it so no need. However, I'm on 13.6 now, so it seems this isn't unique to a version. I see there's been no response here so I have to assume that means it's not a widespread thing. But here I am saying there are at least two of us who haven't been able to figure it out.

Note limited options showing in share menu:

And here's what's enabled for extensions:

I'd love to enable Messages, and I'd love to say I can't because it already is, but clearly it's not an active option for sharing in the share menu, so must be it isn't.

Similar problem except that it applies only to Mail, and the symbol shown is for Gmail (not Apple's own Mail app).

Has anyone found a solution to this problem?