diff --git a/ephy-uri-tester.c b/ephy-uri-tester.c
index fc3eaf3..d90bdef 100644
--- a/ephy-uri-tester.c
+++ b/ephy-uri-tester.c
@@ -987,14 +987,17 @@ G_MODULE_EXPORT void webkit_web_extension_initialize_with_user_data(
 		WebKitWebExtension *ex, const GVariant *v)
 {
 	bool enable = true;
-	const gchar *str = g_variant_get_string((GVariant *)v, NULL);
-	if (str)
+	if (v)
 	{
-		gchar **args = g_strsplit(str, ";", -1);
-		for (gchar **arg = args; *arg; arg++)
-			if (g_str_has_prefix(*arg, "adblock:"))
-				enable = strcmp(*arg + 8, "true") == 0;
-		g_strfreev(args);
+		const gchar *str = g_variant_get_string((GVariant *)v, NULL);
+		if (str)
+		{
+			gchar **args = g_strsplit(str, ";", -1);
+			for (gchar **arg = args; *arg; arg++)
+				if (g_str_has_prefix(*arg, "adblock:"))
+					enable = strcmp(*arg + 8, "true") == 0;
+			g_strfreev(args);
+		}
 	}
 
 	if (enable)