A program running in the backgroud, boot it up, dont open anything and boot it down and see if you have the same problem.
If you dont then next time it happens, click ctrl+alt+del and look to see if any tasks are not repsonding
OnePlus 5T review: Hands-on
Illustrator Andrés Lozano on his improv line work, brazen use of colours & hand sketching
iPhone X review
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