The following CSS rule was added to the javadoc default stylesheet in JDK-8308659 in order to compensate for the `div.horizontal-scroll` causing the margins between module/package/class description and summary tables not collapsing:

section[id$=-description] :is(dl, ol, ul, p, div, blockquote, pre):last-child,
section[id$=-description] :is(dl, ol, ul):last-child > :is(li, dd):last-child {
    margin-bottom:4px;
}

The purpose of this rule is to reduce the bottom margin of the last block element in the main description of a module, package or class. However, since the rules use the descendant combinator it will apply to last-child block tags anywhere in the description.

For example, the rule is applied to "Deprecated" notice, nested lists, and code snippets in module, package and class descriptions. In order to only apply to intended cases, the selectors have to be more specific.