I tried the hex code (javascript strings escaped hex codes). It may depend (to a degree) upon your server and your charset as declared in this sort of meta tag:
HTML Code:
<meta http-equiv="Content-Type" content="text/html; charset=windows-1252">
But, if all that is lined up right (if the named entities work in regular text, it probably is), these both worked locally in three browsers so, should do the job.
Code:
"softstone wei\xdf"
and:
Code:
"slate gr\xfcn-schwarz"
The way this works is that you use the \x prefix and then the two 'digit' hex value of the desired character.
Others, more knowledgeable than I, would know the precise terms for all of these things and if there are any pitfalls to this approach but, it should be serviceable for most of your target audience.
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