Just so you know, I've tweaked the update dialog, based on @Nardog's prototype, for the needs of Convenient-Discussions, adding the ability to choose a preset for screenshots that autofills the description, source, license, and author fields. It still doesn't have a choice of licenses, but makes them available to be typed in manually.

In T360917#9730055, @bwang wrote:

An issue @Jdrewniak pointed out with this approach (and technically any approach that relies on sibling selectors) is that we wont have the correct spacing when elements are floated.

Right, unfortunately p + p will immediately distort the appearance of the majority of articles, and in a noticeable way. Just to be clear: if you apply a fix only to images, something like p + figure + p, you will soon notice that there are also floating tables, floating divs, floating divs preceded by a <link> element from TemplateStyles, groups of floating images, non-floating images, etc. etc. This is volunteers' turf, not developers'; I don't think it's feasible to find any meaningful compromise here and not find yourself (and volunteers) hunting for the endless exceptions for many years to come.

In T360917#9727022, @bwang wrote:

where I consistently apply 0.5em top and bottom padding to <p> elements, except i increase the top margin for “p + p” elements to 1em

The task I closed this in favor of doesn't seem like it's going to be fixed in the near term. It's not even clear if this is a bug and not a feature (although it's not clear to me why CD can't set a tag while DiscussionTools can). Instead, I will just resubmit the form without a tag if tags-apply-blocked error it received.