I've had the same thing happen after an extended period of emulating an Amiga in an interlaced screen mode. After exiting the emulator, there was still similar flickering and mild image retention, that also faded after a few minutes.
My guess is that it's down to the relationship between the specific interlacing used by the panel, if any (lagom.nl has inversion/pixelwalk tests to determine which type a monitor uses), compared to the 60Hz flickering. Something about the two together induces image retention far sooner than the average content, albeit image retention that also fades much quicker.
My guess is that it's down to the relationship between the specific interlacing used by the panel, if any (lagom.nl has inversion/pixelwalk tests to determine which type a monitor uses), compared to the 60Hz flickering. Something about the two together induces image retention far sooner than the average content, albeit image retention that also fades much quicker.