Embedded code blocks and Firefox non-breaking spaces

[DavidM]

Just noticed something strange with embedded code blocks when using Firefox as the browser:

If you copy the text in a code block by selecting it and performing "copy", the spaces in the source seem to be getting converted to non-breaking spaces when you paste it into an application. This wreaks havoc if you are trying to paste the source into something like EMU48.

As far as I can tell, this does not happen with Chrome or Edge, and I haven't tried other browsers yet to see what happens. I've seen a couple posts in other places about this being a result of a recently "fixed" bug in Firefox, so I'm reasonably certain it is the culprit.

Just curious as to whether this is a known issue, and if there are any known workarounds (other than "don't use Firefox").