Mouse cursor disappears when iTunes movie enters full screen

This is not a question... actually I have found a hacking solution to this bug and I wanted to share it with others having the same problem.

Since upgrading to the OS X El Capitan, I am having a problem with my cursor randomly disappearing. It is very repeatable if I start a video in iTunes with the screen maximized and the cursor disappears. In fact, after entering the full screen mode, iTunes hides the mouse cursor which is expectable. The problem is that iTunes can not reappear it again, for example, when I switch to another desktop for doing a temporary job.

Moving the mouse around does nothing, escaping out of full screen mode doesn't make it come back. It is very annoying. As I had never had such a frustrating experience before a fresh install of El Capitan 10.11.3, and upgrading iTunes to 12.3.3, I thought it is all due to the iTunes upgrade. So, I did another fresh install of El Capitan, this time without upgrading iTunes. But the problem still existed. It was interesting that I had this problem only on my MacBook Pro 17" Late 2011, and not with my iMac 21.5" Mid 2009!

After a tiny research, I found that this bug is not because of El Capitan, and it has happened randomly to others for years going as far back as Tiger and may be before.

The only new change that I had done in the System Preferences of my MBP, was in the Accessibility pane, and it was related to zooming. I had always used this feature, but I set the Zoom Style to "Full Screen". This time (after the fresh install of El Capitan), I had changed it to "Picture-in-Picture".

I changed the Zoom Style to "Full Screen" back again, and the problem resolved.

If this doesn't work for you, may be disabling other options, such as "Use keyboard shortcuts to zoom" or "Use scroll gestures with modifier keys to zoom", can resolve the problem.

We all know that this is a bug, and it has been there for a long time. I found that many people had reported this to Apple, but the problem still exists.

For those of you who want to use the "Picture-in-Picture" zooming style, or setting the zoom style to Full Screen does not resolve their mouse disappearing problem, I just mention a few ways to get the mouse cursor back. The following solutions are applied to a disappeared mouse cursor after entering iTunes movie (or any other app) to full screen.

1. Move the mouse before switching the desktop brings the cursor back. Now you can switch the desktop and do whatever you want. (This is the most simple work around, at least to me.)
2. Use Alt-Tab to switch to another program; this will bring the mouse cursor back.
3. Press Ctrl+F2 to activate the Apple menu. (You can also move your cursor far to the top-left and click to activate the menu.)
4. Press Ctrl+Up Arrow (or swipe up with 4 fingers on Track Pad) to activate Mission Control.

You may also find other ways to get your mouse cursor back.

Hope this can help you with disappearing mouse cursor.