ThemeA Theme object represents the specification of a theme.TypeA JSON object that takes the same properties as the "theme" manifest key.Browser compatibilitydesktopmobileChromeEdgeFirefoxOperaSafariFirefox for AndroidSafari on iOSThemeChrome – No supportChromeNoToggle historyEdge – No supportEdgeNoToggle historyFirefox – Full supportFirefox55Toggle historyOpera – No supportOperaNoToggle historySafari – No supportSafariNoToggle historyFirefox for Android – No supportFirefox for AndroidNoToggle historySafari on iOS – No supportSafari on iOSNoToggle history