Why aren't quotation marks copied when I cut'n'paste web page text?

Using Ubuntu 18.04, on both Chrome and Firefox, when I copy and paste text, the quotation marks around <q> tagged text are lost.Notice that all the words are selected, but the two quotation marks aren't. So when I paste the text, the quotation marks don't appear in the result:

The word xxx is inside a <q> tag.

Is this something I have somehow configured incorrectly?

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