Document-based app failing in Mac Catalyst

A document-based app that's been running fine on iPad and Mac Catalyst has stopped working on the Mac as of Sequoia 15.3. After the user selects a document to open, my app never gets called back from Apple's framework. (The app works fine on iPadOS.) Anybody else see this?

I filed a feedback, FB16506048, several weeks ago but have had no reply.

A month has gone by--no response to my FB. My app is dead in the water, and my users are abandoning the app. If I can't deliver and maintain an app, why am I in Apple's developer program?

Document-based app failing in Mac Catalyst
 
 
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