diff --git a/site/source/contexts/DarkModeContext.tsx b/site/source/contexts/DarkModeContext.tsx
index e6c0fc377..0b8f8a85b 100644
--- a/site/source/contexts/DarkModeContext.tsx
+++ b/site/source/contexts/DarkModeContext.tsx
@@ -46,9 +46,18 @@ export const DarkModeProvider: React.FC = ({ children }) => {
 			setDarkMode(e.matches)
 		}
 		const matchDarkMode = window.matchMedia('(prefers-color-scheme: dark)')
-		matchDarkMode.addEventListener('change', onDarkModeChange)
 
-		return () => matchDarkMode.removeEventListener('change', onDarkModeChange)
+		// safari 13 doesn't have addEventListener
+		matchDarkMode.addEventListener
+			? matchDarkMode.addEventListener('change', onDarkModeChange)
+			: matchDarkMode.addListener(onDarkModeChange)
+
+		return () => {
+			// safari 13 doesn't have removeEventListener
+			matchDarkMode.removeEventListener
+				? matchDarkMode.removeEventListener('change', onDarkModeChange)
+				: matchDarkMode.removeListener(onDarkModeChange)
+		}
 	})
 
 	return (
diff --git a/site/source/template.html b/site/source/template.html
index 0bcac3a58..fd53b90b6 100644
--- a/site/source/template.html
+++ b/site/source/template.html
@@ -223,7 +223,7 @@
 		<script>
 			// Set the main colors from the provided customization in the URL We do it
 			// before loading the whole JS bundle to avoid a UI flash. cf. #1786
-			const parseColor = (rawColor) => {
+			function parseColor(rawColor) {
 				try {
 					return JSON.parse(decodeURIComponent(rawColor))
 				} catch (error) {
@@ -233,10 +233,10 @@
 				}
 			}
 			try {
-				let rawColor = new URLSearchParams(
+				const rawColor = new URLSearchParams(
 					document.location.search.substring(1)
 				).get('couleur')
-				let iframeColor = rawColor && parseColor(rawColor)
+				const iframeColor = rawColor && parseColor(rawColor)
 				;[
 					document.documentElement,
 					...document.querySelectorAll('[data-js-color-element]'),