Fwiw, `places.previews.enabled` is not an officially supported pref, it is a reimnant from a different project that potentially we planned to reuse in the future, after an appropriate review pass. The pref is hidden and must be explicitly created.
Bug 2010738 Comment 3 Edit History
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Fwiw, `places.previews.enabled` is not an officially supported pref, it is a reimnant from a different project that potentially we planned to reuse in the future, after an appropriate review pass. The pref is hidden and must be explicitly created. It's a good idea to add some sanity check anyway, and better consider this attack path in the future.