Content-visibility has some issues with Reader interaction (rdar://116776737), and with rendering bugs on bing.com (rdar://116822168). Let's move it to Preview status until we fix some bugs.
<rdar://117079338>
Pull request: https://github.com/WebKit/WebKit/pull/19206
Committed 269480@main (129b13b37051): <https://commits.webkit.org/269480@main> Reviewed commits have been landed. Closing PR #19206 and removing active labels.