Thanks [I'm the author]. I tested with Chrome 105 on macOS and it succeeded. Possibly there are OS/plugin/etc issues?
Of course, I know there is no guarantee that every browsers innerHTML implementation will produce exactly the same result, but so far I haven't found any variation (Chrome, FF, Safari, Edge).
In Firefox 105.0.1 on MacOS, the button also always fails when I click it.
EDIT:
In my case, it appears to be some extra "<div style=\"position: static !important;\"></div>" text added before the closing </body> tag. I suspect this is introduced by a plugin, probably LastPass.
Opps! You're right, the W3C only helped author it.
I was also wrong to say that w3.org never redirects to HTTPS. If the browsers sends a Upgrade-Insecure-Requests HTTP-header, then it redirects. That allows it to support all browsers as securely as possible.
Sites like whynohttps.com and observatory.mozilla.org should really test for this pattern.
Fixel and Hoover are beautiful cats and I am very impressed to see an example. Personally I would be very surprised if this worked considering how territorial cats are.
Honestly, that was my impression at first. But the difference (in hindsight I've never really looked into other apps) is that they actually list ALL files they flag for removal (In Gemini 2 as well) so you do have the option to double check what the app does. You could even let it run in trial (500MB deletion limit) and then plainly look at the list and go delete it manually.
The apps are also not "mass produced", they have really nice animations and you can definitely feel that there has been a lot of effort put into them.
They also make some music player and encryption apps so they're not all cleaning apps.
https://en.wikipedia.org/wiki/Server_Side_Includes