Windows Explorer uses the frame on a certain point of time for video thumbnails. Obviously it's not the first frame as this would often be plain black.
And as Windows advances from Vista, 7, 8 to 10, this time offset also seems to have changed. So I'm thinking there could potentially be a registry value somewhere.
Is there a way to manually define this point in time? - Setting the frame that is being used to be the frame at 00:05:00, for example? What I'm not looking for is a way to use a custom image.
This answer provides a link to a tool that looks primising, but is 7 years old and not up-to-date. So therefore it is not a duplicate.