User:Atmark-chan/custom/toggleOnLiveUpdate.js

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var canonicalPageName = mw.config.get('wgCanonicalSpecialPageName');
if (
    canonicalPageName == 'Watchlist'
    || canonicalPageName == 'Recentchanges'
    || canonicalPageName == 'Recentchangeslinked'
) {
    $('.mw-rcfilters-ui-liveUpdateButtonWidget a').click();
}