diff --git a/src/js/contentscript-extra.js b/src/js/contentscript-extra.js
index 0185a29e7..78689f84c 100644
--- a/src/js/contentscript-extra.js
+++ b/src/js/contentscript-extra.js
@@ -41,7 +41,7 @@ const regexFromString = (s, exact = false) => {
         return new RegExp(match[1], match[2] || undefined);
     }
     const reStr = s.replace(/[.*+?^${}()|[\]\\]/g, '\\$&');
-    return new RegExp(exact ? `^${reStr}$` : reStr, 'i');
+    return new RegExp(exact ? `^${reStr}$` : reStr);
 };
 
 // 'P' stands for 'Procedural'