I click on the link and the ‘update automatically’ button.
It quickly says “Matomo has been successfully updated!” and has the ‘Piwik is now Matomo’ stuff (I’ve got it by now…)
I return to the dashboard, and there’s the update notification again.
Repeat, including after logging out and back in again.
It’s worked on another site and this is the first time this site has had issues with updates like this.