title: Version compatibility of Firefox and the latest Selenium IDE (2.9.1.1-signed)
body: <p>I visited <a href="https://addons.mozilla.org/en-US/firefox/addon/selenium-ide/" rel="noreferrer">https://addons.mozilla.org/en-US/firefox/addon/selenium-ide/</a></p>
  
  <p>to install the latest <strong>Selenium IDE (v 2.9.1)</strong> in Firefox.</p>
  
  <p>My <strong>Firefox version is 54 (64-bit)</strong>
  OS: Windows 10 Pro 64-bit (10.0, Build 14393)</p>
  
  <p>But unfortunately "Add to Firefox" button was shown disabled on the site <a href="https://addons.mozilla.org/en-US/firefox/addon/selenium-ide/" rel="noreferrer">https://addons.mozilla.org/en-US/firefox/addon/selenium-ide/</a></p>
  
  <p>On that site NOTE was found as:
  Note: Selenium IDE will NOT work on Firefox version 55 onwards. Please stay on Firefox version 54 or older.
  <a href="https://i.stack.imgur.com/W1x8U.png" rel="noreferrer"><img src="https://i.stack.imgur.com/W1x8U.png" alt="enter image description here"></a></p>
  
  <p>What can I do to install Selenium IDE on FF 54?</p>