diff --git a/modules/luci-mod-system/htdocs/luci-static/resources/view/system/repokeys.js b/modules/luci-mod-system/htdocs/luci-static/resources/view/system/repokeys.js
index 6703a50970..2b1b757198 100644
--- a/modules/luci-mod-system/htdocs/luci-static/resources/view/system/repokeys.js
+++ b/modules/luci-mod-system/htdocs/luci-static/resources/view/system/repokeys.js
@@ -117,7 +117,7 @@ function removeKey(ev) {
 }
 
 function isPemFormat(content) {
-	return /-BEGIN ([A-Z ]+)?PUBLIC KEY-/.test(content);
+	return new RegExp('-BEGIN ([A-Z ]+)?PUBLIC KEY-').test(content);
 }
 
 function keyEnvironmentCheck(key) {