diff --git a/popup/config.html b/popup/config.html
index c848757051ddf95cabed88e52fffee8d51eec436..8756209cd8f19e2136acde1b7c3a48bfb89cb7ad 100644
--- a/popup/config.html
+++ b/popup/config.html
@@ -18,9 +18,7 @@
 <div class="container">
 
 	<!-- MAIN SCREEN  --> 
-	<div id="main_screen">		
-		<center>
-
+	<div id="main_screen" style="text-align:center">		
 			<table class="standard_table">
 				<tr>
 					<td style="text-align:left"><h2 class="title"> SIMPLE MODIFY HEADERS  </h2>  </td>
@@ -89,8 +87,6 @@
 				</tr>
 		</table>
 
-		</center>
-
 	</div>
 
 	<!-- PARAMETERS SCREEN -->
diff --git a/popup/config.js b/popup/config.js
index 5bff9c52efd1d6fbcd79895c0fcb4bd8771cb82e..ed6f1e5adb53969cd0c518be7c609bb5ca672502 100644
--- a/popup/config.js
+++ b/popup/config.js
@@ -195,7 +195,7 @@ function create_configuration_data() {
   let headers = [];
   let debug_mode=false;
   let show_comments=false;
-  for (i=0;i<tr_elements.length;i++) {
+  for (let i=0;i<tr_elements.length;i++) {
     const url_contains = tr_elements[i].childNodes[0].childNodes[0].value;
     const action = tr_elements[i].childNodes[1].childNodes[0].value;
     const header_name = tr_elements[i].childNodes[2].childNodes[0].value;