“Startup Failed” “DatabaseError(message: “file is not a database”, code: 26”

Attempting to launch Avast Secure Browser, a brief flash of something, then the entire page reads:

“Startup Failed” “DatabaseError(message: “file is not a database”, code: 26”

No app update is available in AppStore. Recently updated to iOS 15.7 on iPad Air Gen. 5. I haven’t tried ASB in a while so uncertain when this problem might have begun.