diff --git a/popup/popup.js b/popup/popup.js
index ad6fdd81..5490fae4 100644
--- a/popup/popup.js
+++ b/popup/popup.js
@@ -172,7 +172,7 @@ function initPopup() {
         $('label', info).textContent = t('unreachableAMO');
         const note = (FIREFOX < 59 ? t('unreachableAMOHintOldFF') : t('unreachableAMOHint')) +
                      (FIREFOX < 60 ? '' : '\n' + t('unreachableAMOHintNewFF'));
-        const renderToken = s => s[0] === '<' ? $create('b', s.slice(1, -1)) : s;
+        const renderToken = s => s[0] === '<' ? $create('b', tWordBreak(s.slice(1, -1))) : s;
         const renderLine = line => $create('p', line.split(/(<.*?>)/).map(renderToken));
         const noteNode = $create('fragment', note.split('\n').map(renderLine));
         const target = $('p', info);