Cursor on mac gets stuck when sharing screen with airplay: WORKAROUND SOLUTION
I'm posting this as a workaround solution to the airplay mirroring bug asked by a community member, from year 2018. I experienced the same frustration and as the answer given by the "specialist" was less then an adequate try, I managed to reproduce the issue and found the following workaround solution... I hope it is helpful for someone who experiences a similar bug.
"Sometimes when I share my MacBook Pro screen to my Apple TV via airplay, my cursor will get stuck in the left 1/4 of the screen. It's like it hits a wall and won't move to the right beyond the left portion of my screen. The only way I've found to fix it is to shut down the computer. Any ideas why this happens?"
The bug reproduction:
In my case, the bug happens when arrangement of the displays is set in such a way that the built-in display of the mac is set to be oriented at the LEFT side of the second display (connected via airplay) and "Mirror displays" option is ticked. Since mirror display option is ticked, naturally you cannot drag and move the second display but the system still has a memory of the orientation when not mirrored. Only then, when the is Airplay display mirroring is initiated (as mirror displays is ticked) and when the mouse curser was at the leftside 1/4 quarter of the screen during this initiation (This can be the case if airplay is selected thorugh System Preferences/Displays window and the window opens up at the lefthand-side of the screen.), cursor gets blocked as if by an invisible vertical barrier and can not be moved to the middle or right side of the screen when AirPlay is initiated. (Also, if I initiate the Airplay from the menu bar, where airplay icon and submenu is at the top right corner of my screen, this bug did not happen as the cursor was already at the righthand-side)
The Workaround:
I managed to avoid this bug by first unticking "Mirror Displays" and then dragging my second display so that the built-in display stays at the Right side of the second display. Then clicked "Mirror Displays" and enabled Airplay (with my cursor at the lefthand-side if the screen): Voila! the cursor is no longer stuck.
TL;DR:
1)Turn off AirPlay
2)System Preferences/Displays/Arrangement: Disable "Mirror Displays"
3) Drag the second screen so that built-in display is at the RIGHT side of the second display
4) Re-enable "Mirror Displays"
5) Initiate AirPlay
Windows