It's their machine so they must answer which drivers to use on Windows 10. This sounds like a driver or setting issue. Back to HP.com and try their chat link.
I'm using an HP Stream upgraded from Win 8.1 to Win 10. All is well as long as I do not try to run a search engine while connecting my desktop to my TV monitor as my external display. Oh, aside from the fact that the actual desktop extends slightly behind the frame of the monitor, leaving me guessing at where "Start" is, for instance.
I've learned to work with the half-hidden icons and invisible choices for the "Power" button. But what I cannot figure out is the weird super-fast flashing on-off that happens as soon as I try to use a web-based text box. I can click the cursor into the box, but as soon as I enter the first character, everything goes haywire. So far, the only "out" is to totally shut down, and I cannot even do *that* at first, because when I shut down the browser window, all the desktop icons disappear. Then I have to blindly guess at where the "start" menu is, and hope I don't have to do a hard power-off.
This behavior has held true for both Chrome and Firefox browsers. I've also tried reinstalling drivers and even completely resetting Windows 10 in my attempts to solve this problem. When I try to research, the only mention of "flashing" I've found relate to the original Win 10 problems from 9 months ago.

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