Unfortunately, the problem appears again even when I remove the disable-library-validation entitlement.

Thank you for your suggestion. It's hard for us to follow, because the code that installs the new version during an update comes from Chromium, not us. In the meantime, I have figured out what "causes" the problem. Brave uses the com.apple.security.cs.disable-library-validation entitlement. Removing it fixes the problem. Unfortunately, we don't yet know whether we will be able to do this in production code. Would you happen to have another suggestion, given the info about the entitlement?

Sorry for the many duplicate comments. The forum gave me errors when I wrote them, that they couldn't be submitted. Now, I see that they actually did get submitted.

Thank you. The WWDC video says that apps signed by the same developer accoun or team can update each other. Unfortunately, this does not seem to be true: I created two apps with Xcode: TestApp and TestUpdater. They launch fine, are signed with the same certificate and pass Gatekeeper. Both apps lie in /Applications and are owned by my user. On launch, TestUpdater tries to create a folder inside TestApp. This fails with the same permission error I described at the top.

Thank you. The WWDC video says that apps signed by the same developer accoun or team can update each other. Unfortunately, this is not true in my tests.

Thank you. The WWDC video says that apps signed by the same developer accoun or team can update each other. Unfortunately, this does not seem to be true: I created two apps with Xcode: TestApp and TestUpdater. They launch fine, are signed with the same certificate and pass Gatekeeper. Both apps lie in /Applications and are owned by my user. On launch, TestUpdater tries to create a folder inside TestApp. This fails with the same permission error I described at the top.

Thank you. The WWDC video says that apps signed by the same developer accoun or team can update each other. Unfortunately, this does not seem to be true: I created two apps with Xcode: TestApp and TestUpdater. They launch fine, are signed with the same certificate and pass Gatekeeper. Both apps lie in /Applications and are owned by my user. On launch, TestUpdater tries to create a folder inside TestApp. This fails with the same permission error I described at the top.

Thank you. The WWDC video says that apps signed by the same developer accoun or team can update each other. Unfortunately, this does not seem to be true: I created two apps with Xcode: "TestApp" and "TestUpdater". They launch fine, are signed with the same certificate and pass Gatekeeper (spctl --assess). Both apps lie in /Applications and are owned by my user. On launch, TestUpdater tries to create a folder inside TestApp. This fails with the same permission error I described at the top.

Thank you. The WWDC video says that apps signed by the same developer accoun or team can update each other. Unfortunately, this does not seem to be true: I created two apps with Xcode: "TestApp" and "TestUpdater". They launch fine, are signed with the same certificate and pass Gatekeeper (spctl --assess). Both apps lie in /Applications and are owned by my user. On launch, TestUpdater tries to create a folder inside TestApp. This fails with the same permission error I described at the top.

Thank you. The WWDC video says that apps signed by the same developer accoun or team can update each other. Unfortunately, this does not seem to be true: I created two apps with Xcode: "TestApp" and "TestUpdater". They launch fine, are signed with the same certificate and pass Gatekeeper (spctl --assess). Both apps lie in /Applications and are owned by my user. On launch, TestUpdater tries to create a folder inside TestApp. This fails with the same permission error I described at the top.