You can install old XUL version 23.3.1, but you should use Firefox 56 or eariler one.
https://addons.mozilla.org/en-US/firefox/addon/fvd-speed-dial/versions/
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You can install old XUL version 23.3.1, but you should use Firefox 56 or eariler one.
https://addons.mozilla.org/en-US/firefox/addon/fvd-speed-dial/versions/