You have to quote attribute values with "
(QUOTATION MARK) or '
(APOSTROPHE), not “
(LEFT DOUBLE QUOTATION MARK) and ”
(RIGHT DOUBLE QUOTATION MARK).
This type of error is typically caused by writing code using a word processor (such as Microsoft Word or Apple Pages) with automatic replacement of quotes with typographic quotes (aka Smart Quotes) enabled. Try using a text editor (such as Visual Studio Code, Sublime Text, Komodo Edit, Emacs, or Vim) instead.
The other common cause for this error is copy/pasting code from a website where the author has let a WordProcess CMS or similar mangle their input in the same way as a word processor. Check code you are copy/pasting carefully.
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