- Type
about:configin the browser address bar. - Set
devtools.inspector.showUserAgentShadowRootstotrue// not needed for Firefox 76+ - Set
devtools.inspector.showAllAnonymousContenttotrue(Firefox 76+)
about:config in the browser address bar.devtools.inspector.showUserAgentShadowRoots to true // not needed for Firefox 76+devtools.inspector.showAllAnonymousContent to true (Firefox 76+)