Most questions about app links not working are about app links navigating to Play Store even when the app is installed (instead of launching the app).

I have the opposite problem. When the app is installed, the app link works as expected. But when the app is not installed, the link just opens in the browser. I doublechecked https://domain/.well-known/assetlinks.json and ran all the possible validation tools. I’m also relatively certain it used to work until a few weeks ago.

Any ideas what am I missing?