"If you’d like to turn these features off, open about:config in the Firefox address bar, search for browser.ml.enable, set it to false, and that should disable everything."
This is nice to know but in future versions of Firefox that single config switch (browser.ml.enable) will both change names and split into multiple sub-switches, most likely appearing in different pages of about:config.
These sub-switches will then not remain consistent.
Bank on it.
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