Lightroom Classic doesn't republish changed videos

If an existing collection in Publish Services includes a video, and then I modify the video (say, with Quick Develop), Lightroom correctly moves the video to the "Modified Photos to Republish" section. When I click Publish, Lightroom goes through the motions of updating the published collection and moves the video back to the "Published Photos" section.

However, this happens so quickly that it isn't possible that the modified video actually got uploaded. Indeed, if I look at the published video at the external site, the modifications haven't been applied.

I can remove the video from the collection, click Publish, then re-add the video (from All Photographs), then click Publish again. Then the video is published with the modifications, and everything is fine.

Apparently, Lightroom is losing track of the need to regenerate and upload the changed video in this situation. Perhaps it is behaving as if there were only a metadata change.

I am using the SmugMug publish service. I tried the same experiment with the Hard Drive publish service, and it worked correctly. (I don't use other publish services, so I haven't experimented with them.)

[Moved from ‘Bugs’ to ‘Discussions’ by moderator, according to forum rules.]