macOS 10.14 Mojave issues for "Folder Compare"

[StasD]

Hello,
After upgrading to macOS 10.14 Mojave, BC cannot now scan many subfolders in "Library" folder which it previously did not have any problem scanning. Says "Operation not permitted" in the log. Among the affected folders are various Safari folders, Mail, etc. For some other folders it officially asks for permissions (e.g. Contacts, Calendars, Photos).
Another weird thing is that I was trying to run it as 'root' (using "sudo" in command line), and it did not seem to help at all...
Are you able to fix BC so that it behaves in Mojave as it does in earlier versions of macOS?
Thanks.

[Aaron]

Hello,

It looks like there's been a change in how MacOS protects the Library folder. In 10.13, Access Denied is thrown, while running with sudo can workaround this. 10.14 has a new method of prompting for access, while also preventing access even with sudo. It is likely this is an intentional protection, and may not be something we will be able to workaround without larger, underlying changes that we're working on for the 64bit build.

Update: I should add this depends on if MacOS intends to allow this level of access for 3rd party applications with 10.14+. This will require investigation.

[dempson]

There is indeed a new security mechanism in 10.14: a new privacy feature prevents applications from accessing certain data in the user's home folder, including Mail, Messages, Safari, Home, plus Time Machine backups and some administrative settings.

The user gets to decide which applications to trust.

To grant the current version of Beyond Compare access to those locations:

1. System Preferences.
2. Security & Privacy.
3. Privacy tab.
4. Full Disk Access (in the left column). The description on the right mentions the protected areas.
5. Click the padlock to make changes and enter your admin username and password.
6. Click the + button under the list of applications.
7. Navigate to the Applications folder and choose Beyond Compare.

You should now see Beyond Compare in the list of applications with full disk access and it is enabled. If you want to revoke Beyond Compare's access again, you just need to untick the checkbox (after authenticating as an administrator).

I've tested this as far as confirming it allows Beyond Compare to browse into ~/Library/Mail. Without the setting I got an access violation.

A future update to Beyond Compare might be able to make this process easier, e.g. if there is a mechanism by which Beyond Compare can indicate to the OS that it would like to have full disk access (probably in the application's Info.plist) then it will appear in the Full Disk Access list automatically, but the user would still need to enable access via System Preferences. Beyond Compare could also display an explanation if the user tries to access a protected area and the setting is not enabled. I've seen similar prompts from other applications for other privacy mechanisms.

[StasD]

Wow... Adding "Beyond Compare" to the "Full Disk Access" group did indeed fix all the issues with folder access. Many thanks!
Hope Aaron will figure it out how to deal with these new restrictions so the upcoming 64 bit build manages these settings in more straightforward manner!

[Aaron]

Thanks, dempson. That's exactly what I didn't know about and needed to find. I'll add these notes to our tracker entry on the subject.