Bug 1737434 - Update SeaMonkey website for 2.53.10 beta 1 release - update known issues. r=frg

src/releases/seamonkey2.53.10/index.en.html

@@ -539,6 +539,10 @@ Please read this before reporting any new bugs.
   <li>If you try to start SeaMonkey using a locked profile, it will crash (see <a
     href="https://bugzilla.mozilla.org/show_bug.cgi?id=573369">bug 573369</a>).
   </li>
+  <li>In ChatZilla users are unable to add an exception for an invalid
+    certificate unless an override is added to the preferences (see <a
+    href="https://bugzilla.mozilla.org/show_bug.cgi?id=1738597">bug 1738597</a>).
+  </li>
   <li>Linux:
     <ul>
       <li>SeaMonkey 2.53.7b1 can not be automatically updated to later beta