Can’t share photos from Photos app to Messages on Catalina

[reubs]

My wife got a new MBP recently, and upon restoring it from a time machine backup, she’s been trying to figure it out.

Last night, looking through her old iPhoto/new Photos library, she realized she couldn’t send photos via iMessage. She’s signed into iCloud on her message app, but “messages” is not available as a share option from the share menu.

Any help or advice here? I’m at a complete loss since I don’t have a Catalina (or any modern) Mac of my own.

 

[26139]

Is she signed in to her iCloud account in System Preferences?

Under Extensions in System Preferences, is Messages checked?

Messages is not just grayed out in Photos, it doesn't exist as an option at all?
Do any others?