The way it works on gwern.net is that the LaTeX is processed into CSS/HTML by Mathjax but a copy of the original LaTeX is preserved; this would copy-paste as gibberish, but some Javascript will detect any copy-paste and swap out the gibberish for the original LaTeX without the user having to do anything. (This ‘copy-paste listener’ also does some other things like remove invisible Unicode characters which are there for typesetting but would be a nuisance in anything copy-pasted.)
Looking at the LW2 HTML source, it seems to preserve the original LaTeX in much the same way, so it should be quite easy for LW2 to copy our copy-paste listener approach. (I’m a little surprised that GW doesn’t seem to do that already, actually; Obormot just forgot to port it over.)
The way it works on gwern.net is that the LaTeX is processed into CSS/HTML by Mathjax but a copy of the original LaTeX is preserved; this would copy-paste as gibberish, but some Javascript will detect any copy-paste and swap out the gibberish for the original LaTeX without the user having to do anything. (This ‘copy-paste listener’ also does some other things like remove invisible Unicode characters which are there for typesetting but would be a nuisance in anything copy-pasted.)
Looking at the LW2 HTML source, it seems to preserve the original LaTeX in much the same way, so it should be quite easy for LW2 to copy our copy-paste listener approach. (I’m a little surprised that GW doesn’t seem to do that already, actually; Obormot just forgot to port it over.)