In my case, the subtitles in Netflix are bigger than I set in the settings. I see the right size subtitles in Amazon Prime.

Not sure what you mean by "where do you get each". For example, using CFURLCreateFromFSRef produces: warning: 'CFURLCreateFromFSRef' is deprecated: first deprecated in macOS 10.9 - Not supported [-Wdeprecated-declarations]

Yes, I know FSRef is deprecated. I have some legacy code with FSRef all over the place, and it's hard to budget a man-month to fix something that's not actually causing problems for users. To give just one example of where an FSRef might come from, some legacy data might contain an old-fashioned Alias handle, so I need to call FSResolveAlias.

After I trashed my app and rebuilt, the points of interest started showing up. It was not necessary to change 99 to OS_SIGNPOST_ID_EXCLUSIVE. Weird. I had tried running under the debugger to verify that the code was getting hit, so I don't see how I could have been running old code. I don't know if this is relevant, but the code I was trying to profile is not in the main app code, but in a private framework built by a subproject that is a target dependency.

The problem is, I'm not the one calling CFRunLoopPerformBlock, it's some Apple code (AppKit or Core Animation or what have you) when a subview is added. So I have no control over the mode.

Thanks for your advice. As for your proposed long-term solution, I don't know much about app extensions, and I don't see how that would solve the problem. It still wouldn't be an app, right, so how could SMAppService be used in it?

In Swift, NSTask is called the Process class.

The documentation for CGEventTapCallBack does say that your callback can return NULL to delete the event, which would be reasonable to do if you have fully handled it.

@benson3816 As far as I know, there is no side-effect to repeatedly creating event taps, so long as you clean up afterward as shown in my code.

@juliencrypt The user can grant full disk access in System Settings>Privacy & Security>Full Disk Access. See also https://stackoverflow.com/questions/55883217/mac-app-to-prompt-user-for-full-disk-access .

If they changed the behavior now of a feature that has been there since macOS 10.15, there'd be a risk of breaking existing code.

Doesn't work for me on Sequoia. I get a partial printout, 11 of 13 pages.