anecdotal reports are that this makes Firefox noticeably faster

that list of settings to disable:

browser.ml.enable
browser.ml.chat.enabled
browser.ml.chat.menu
browser.ml.chat.page
browser.ml.chat.page.footerBadge
browser.ml.chat.page.menuBadge
browser.ml.linkPreview.enabled
browser.ml.pageAssist.enabled
browser.tabs.groups.smart.enabled
browser.tabs.groups.smart.userEnabled
extensions.ml.enabled
browser.search.visualSearch.featureGate

    browser.ml.enable
    browser.ml.chat.enabled
    browser.ml.chat.menu
    browser.ml.chat.page
    browser.ml.chat.page.footerBadge
    browser.ml.chat.page.menuBadge
    browser.ml.linkPreview.enabled
    browser.ml.pageAssist.enabled
    browser.tabs.groups.smart.enabled
    browser.tabs.groups.smart.userEnabled
    extensions.ml.enabled
    browser.search.visualSearch.featureGate
0
0
0

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