diff --git a/core/src/utils/config.ts b/core/src/utils/config.ts
index 239cacf881..bc0a6789a3 100644
--- a/core/src/utils/config.ts
+++ b/core/src/utils/config.ts
@@ -24,7 +24,7 @@ export function configFromURL() {
     .split('&')
     .map(entry => entry.split('='))
     .map(([key, value]) => [decodeURIComponent(key), decodeURIComponent(value)])
-    .filter(([key]) => key.startsWith(IONIC_PREFIX))
+    .filter(([key]) => startsWith(key, IONIC_PREFIX))
     .map(([key, value]) => [key.slice(IONIC_PREFIX.length), value])
     .forEach(([key, value]) => {
       config[key] = value;
@@ -32,3 +32,7 @@ export function configFromURL() {
 
   return config;
 }
+
+function startsWith(input: string, search: string): boolean {
+  return input.substr(0, search.length) === search;
+}