Last I checked, it’s a polyfill that Chrome won’t default include - they’re just saying that they’d have a polyfill in JS and it’s on site authors to use.
That breaks old unmaintained but still valuable sites.
That breaks old unmaintained but still valuable sites.
(But of course, XML Stylesheets are most widely used with RSS feeds, and Google probably considers further harm to the RSS ecosystem as a bonus. sigh)
Fortunately, Thunderbird still has support for feeds and doesn't seem to have been afflicted by the same malaise as the rest of the org chart. Who knows how long that will last.
I completely understand the security and maintenance burdens that they're bringing up but breaking sites would be unacceptable.