Simon Pieters

Good point, fixed.

I'm not aware of plans of it being implemented for `ping`. Scripting is disabled check is used by lazy-loading, which is implemented ([see wpt](https://wpt.fyi/results/html/semantics/embedded-content/the-img-element/image-loading-lazy-in-script-disabled-iframe.html?label=master&label=experimental&aligned&q=lazy)). However, CSS can probably be used...

I removed the scripting is disabled check.

I filed https://github.com/whatwg/html/issues/11804 , I can review this again when that is fixed. I would suggest adding tests in this area that check which UA styles are applied, see e.g....

Some of the linked tests are tentative, is there a PR to make them not tentative?

From https://nerdydata.com/ ("We index approximately 160 million websites") searching in "Deep Web": ``` src="//www.youtube.com/v/ Showing 1 - 50 (of approx. 22,090 found) src="http://www.youtube.com/v/ Showing 1 - 50 (of approx. 281,530...

For comparison, we have ``: ``` A start tag whose tag name is "image" Parse error. Change the token's tag name to "img" and reprocess it. (Don't ask.) ```

Couldn't most of the "rewriting" be done by YouTube instead of in the browser engine, though? That is, if the only hack in the browser engine is `type="application/x-shockwave-flash"` -> `type="text/html"`...

Can Chromium also implement a use counter?

OK, great. As far as I can tell, Gecko only rewrites for Youtube ([here](https://searchfox.org/mozilla-central/source/dom/base/nsObjectLoadingContent.cpp#681)). I'll check if we've received web compat issues for dailymotion/vimeo embeds.