diff --git a/web-extension/extractHtml.js b/web-extension/extractHtml.js
index 328e8aa..3975b0d 100644
--- a/web-extension/extractHtml.js
+++ b/web-extension/extractHtml.js
@@ -328,7 +328,7 @@ function extractCss(appliedStyles, callback) {
                     if (!classNames) {
                         classNames = pre.getAttribute('id');
                         if (!classNames) {
-                            classNames = pre.tagName;
+                            classNames = pre.tagName + '-' + Math.floor(Math.random()*100000);
                         }
                     }
                     var tmpName = cssClassesToTmpIds[classNames];
diff --git a/web-extension/utils.js b/web-extension/utils.js
index a218918..70f299b 100644
--- a/web-extension/utils.js
+++ b/web-extension/utils.js
@@ -188,7 +188,7 @@ function getAbsoluteUrl(urlStr) {
 
 function removeEndingSlash(inputStr) {
     if (inputStr.endsWith('/')) {
-        return inputStr.substring(0, inputStr.length - 2);
+        return inputStr.substring(0, inputStr.length - 1);
     }
     return inputStr;
 }