An alternative fix on the CSS level would be doing clear: both to transfer the blame away from reference wrappers.

I don't see how that fixes the possible objection--it just moves the whitespace to above the div from beside the div.

In T160830#3112268, @Izno wrote:

An alternative fix on the CSS level would be doing clear: both to transfer the blame away from reference wrappers.

I don't see how that fixes the possible objection

A CSS-level workaround would only require a single point of change to achieve generally acceptable (I guess) layout. Many objections on zhwp are, in fact, objection to "breaking" pages with possibly intentional single-column references and requiring a large volume and edits to fix.

it just moves the whitespace to above the div from beside the div.

Since most of these floats are portal/Commons/Wikisources links (none of which appear particularly tall), doing such a move should make the big wasted space smaller, and this problem will appear more tolerable. To quote a Chinese proverb, this quick workaround is essentially taking bricks from the wall on the east to fix the one on the west…

An alternative fix on the CSS level would be doing clear: both to transfer the blame away from reference wrappers.

Oppose to use such clear:both method because it would make the layout more strange in those cases, refer to this testing.

Why <references /> instead of just <references>? Isn't it now broken following RemexHtml?

In T160830#4295086, @Liuxinyu970226 wrote:

Why <references /> instead of just <references>? Isn't it now broken following RemexHtml?

<references/> is not an HTML tag. Even if it were, only certain HTML tags cannot be self-closed. Regardless, your question is irrelevant to this task.