My mouse pointer is now disappearing when moving into the browser search bar and also while typing this post if I move the mouse pointer outside of the box im typing in it dissapears when I move it back into the box
There may be a setting in Mouse in Control Panel about "Hide while typing", change it. It should apply to any dialog box one can type in. But do keep in mind the Build you show is the Insider Preview, a 'test' version of Win10. As such if things don't work as desired you can report the problem to Microsoft.
Oops, forgot to mention Control Panel and its features is now in Settings.
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