Jacco Flenter

I experimented a bit with adding `pointer-events: none;` to the `.xterm-accessibility` element. This seems to restore the copy/paste functionality while maintaining the screenreader functionality (this last thing was tested with...

The problem is caused by the `.xterm-accessibility` element, which has a z-index of 10 (in release 4.4.0, see: https://github.com/xtermjs/xterm.js/blob/4.4.0/css/xterm.css#L153) In my project's stylesheet i've added a z-index to`.xterm-viewport` as well...