You click a link to a news site, to read an article that seems interesting.
On the page that loads there is the article, but also, somewhere on the right, often near the bottom, there is a small video player. Inexplicably, it was not blocked by your ad-blocker.
It is auto-playing a news video that is not connected to the article. Sound is often on.
@zeruch @rysiek MIL-SPEC
<BLINK> is ok, right? https://bugzilla.mozilla.org/show_bug.cgi?id=213625