--- a/browser/base/content/browser.js
+++ b/browser/base/content/browser.js
@@ -4939,16 +4939,28 @@ var CombinedStopReload = {
     // we get notified of document loads.
     if (!stop || !reload)
       return false;
 
     this._initialized = true;
     if (XULBrowserWindow.stopCommand.getAttribute("disabled") != "true")
       reload.setAttribute("displaystop", "true");
     stop.addEventListener("click", this);
+
+    // Removing attributes based on the observed command doesn't happen if the button
+    // is in the palette when the command's attribute is removed (cf. bug 309953)
+    for (let button of [stop, reload]) {
+      if (button.hasAttribute("disabled")) {
+        let command = document.getElementById(button.getAttribute("command"));
+        if (!command.hasAttribute("disabled")) {
+          button.removeAttribute("disabled");
+        }
+      }
+    }
+
     this.reload = reload;
     this.stop = stop;
     this.stopReloadContainer = this.reload.parentNode;
     this.timeWhenSwitchedToStop = 0;
 
     if (this._shouldStartPrefMonitoring) {
       this.startAnimationPrefMonitoring();
     }