Feature Request: Set chapter thumbnail time different than chapter start time

[Erik Van Benschoten]

Being a bit of an OCD completionist I find myself wanting to have the chapter thumbnails match those that are available in DVD/Blu-Ray/etc. menus. Is there a way to alter the UI to specify the time for a chapter thumbnail? I tried using a separate chapter list that has the preferred thumbnail time to generate the chapter previews, but that seems to generate a bogus chapter 0 thumbnail.

[Erik Van Benschoten]

Attached is a proposed idea for the UI for this feature - in red text on the right.