diff --git a/phpBB/styles/prosilver/template/overall_header.html b/phpBB/styles/prosilver/template/overall_header.html
index 4438137f7d..09824d0a16 100644
--- a/phpBB/styles/prosilver/template/overall_header.html
+++ b/phpBB/styles/prosilver/template/overall_header.html
@@ -33,7 +33,7 @@
 <script>
 	WebFontConfig = {
 		google: {
-			families: ['Open+Sans:600:cyrillic-ext,latin,greek-ext,greek,vietnamese,latin-ext,cyrillic']
+			families: ['Open+Sans:300,300i,400,400i,600,600i,700,700i,800,800i&subset=cyrillic,cyrillic-ext,greek,greek-ext,latin-ext,vietnamese']
 		}
 	};
 
diff --git a/phpBB/styles/prosilver/template/simple_header.html b/phpBB/styles/prosilver/template/simple_header.html
index 0e889b476d..905d25096f 100644
--- a/phpBB/styles/prosilver/template/simple_header.html
+++ b/phpBB/styles/prosilver/template/simple_header.html
@@ -11,7 +11,7 @@
 <script>
 	WebFontConfig = {
 		google: {
-			families: ['Open+Sans:600:cyrillic-ext,latin,greek-ext,greek,vietnamese,latin-ext,cyrillic']
+			families: ['Open+Sans:300,300i,400,400i,600,600i,700,700i,800,800i&subset=cyrillic,cyrillic-ext,greek,greek-ext,latin-ext,vietnamese']
 		}
 	};