In some cases, #535 caused comment display to wildly break visible
page formatting. The sidebar often moved to bottom of page, and some
comments would display in a second column alongside the main one.
Root cause was a closing `</div>` left outside of a conditional
which was included in rendered markup even when:
1) A comment is invisible for the current browsing user v, e.g.
filtered or removed.
2) The subtree rooted at said comment is to be hidden based on
the display logic added in #535.
Which left a stray `</div>` with no opening tag where those
comments should've gone.
Most of the testing appears to have been done on reply chains of
comments, which behave correctly. It is specifically the zero
children (or otherwise not even showing a "Removed" message in the
page) which causes the bug.
b04849e5b7