diff --git a/handlers/image.js b/handlers/image.js
index 7bdeab0..09962d0 100644
--- a/handlers/image.js
+++ b/handlers/image.js
@@ -26,11 +26,11 @@ module.exports = browser => async (req, res) => {
         filter: n => {
           // %[00 -> 19] cause failures
           if (
-            n.innerText && n.innerText.match(/%[0-1][0-9]/) &&
+            n.innerText && n.innerText.match(/%\S\S/) &&
             n.className &&
             n.className.startsWith('cm-') // is CodeMirror primitive string
           ) {
-            n.innerText = n.innerText.replace('%', '%25')
+            n.innerText = encodeURIComponent(n.innerText)
           }
           if (n.className) {
             return String(n.className).indexOf('eliminateOnRender') < 0