How a security feature trying to block malicious documents has rendered a Finder feature useless, causing users and developers problems.
LaunchServices
Two sets of log excerpts demonstrate how macOS can prevent a user from opening a document, then mislead them into thinking it’s the app at fault.
You double-click to open a document, and see a security alert telling you it’s from an unidentified developer and your security settings prohibit opening. What the hell?
Repairing LaunchServices database, rebuilding it from scratch, and controlling individual app entries – all using this undocumented command.
Sometimes macOS decides you want to open documents using the wrong version of the right app. Here’s how to fix that.
How can the Open Recent menu offer to open a document that no longer exists when the volume it was on is no longer mounted?
You try to open a document – in this case, one of Firefox’s bookmarks – and nothing happens. What could be wrong? It turns out it’s a bug, of course. But where?
Mojave checks newly-installed apps which are not from the App Store more thoroughly, and handles notarized apps differently too. Here are some details.
Last of 3 articles explains how macOS selects and starts the app with which to open a document which you double-clicked/tapped.
Second of 3 articles explains how macOS puts documents through its security checks before opening them.
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