I've had and still have this issue with several monitors. At first I thought it was only the ones that came with an external power brick, and not the ones with an internal PSU, but no it seems completely random. This only happens in fall, winter, and spring when the air is dry, and grounding your PC or monitor does nothing to solve that. For me it happens when I tilt up my DXRacer chair after a while, but also happens with my IKEA Markus chair.
At this point I'm pretty sure it's caused by ESD being created from the friction on the wheels of my chairs, when rolling around on the protective plastic mat which is on my wooden floor. Probably the only way to get rid of it, is buying an anti-static floor mat, and those can be a bit expensive depending on where you're located. But so far from 4 different monitors I've owned, none of them have taken any damage whatsoever from this, and all of them are still functioning from what I know (some been sold off).