Address

Undoing the user agent italic on address, and the paragraph spacing that would otherwise break it apart.

base/address.css exists to undo two things rather than to add any.

address {
  font-style: normal;
  margin-block: 0;

  p {
    margin-block: 0;
    text-wrap: unset;
  }
}
RuleUndoes
font-style: normalThe user agent italic, which reads as emphasis rather than as contact details
margin-block: 0The block margin, left to the surrounding layout
p { margin-block: 0 }The paragraph rhythm, which would space the lines of a single address apart
p { text-wrap: unset }text-wrap: pretty from the reset

Why text-wrap is reset

The reset applies text-wrap: pretty to every p, which tunes the wrapping of running prose by avoiding a short last line. An address is a stack of short deliberate lines, usually broken with <br>, so there is nothing for the algorithm to improve and it can only move a break the author chose.

unset rather than nowrap: the address still wraps if it has to, it simply stops being treated as prose.

Markup

<address>
  Un Cinq<br>
  12 rue de la Paix<br>
  75002 Paris
</address>

<address> is for the contact details of the nearest <article> or of the document, not for arbitrary postal addresses in body text. Using it as a generic address wrapper gives a screen reader a contact landmark that is not one.

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