[Feature request] Add chapter marker or any indicator on the seekbar

[rieje]

This addon does awesome stuff but I think an option to add chapter marker (or any indicator) on the seekbar where the bookmark was made is useful for e.g. making video edits (ideally the chapter marker is saved to a file compatible to losslesscut, an ffmpeg GUI lossless editor). Being able to see the bookmarks on the seekbar also gives a sense of perspective of the context of the portion of the video you've bookmarked.