[elorant]

There's noscript.

https://noscript.net/

[cygx]

It's not a complete replacement, though. For example, a couple of months ago we had a discussion about websites scanning local ports, prompted by [1]. This can in fact be done without Javascript, in which case uMatrix would still protect you, whereas NoScript would not.

[1] https://nullsweep.com/why-is-this-website-port-scanning-me/

[shawnz]

How can this be done without JavaScript in such a way that uMatrix could still block it?

[cygx]

If you wanted to check if port 42 is open, have a

    <link rel="stylesheet" href="http://127.0.0.1:42">

followed by an

    <img src="http://example.org/?port=42">

The <img> won't be requested until the stylesheet has failed to load, which takes a different amount of time depending on whether there was something listening on that port, or not.

uMatrix won't allow the request to the local machine to go through.