Note: Turning off the automatic update of Firefox is not recommended. Only the latest version of Firefox gets regular security updates and will keep you safe and sound on the internet.
However, if you really need to turn off the automatic update of Firefox, please follow these steps: In the Firefox window, click the Firefox button at the top, then select the Options menu item.
- If no Firefox button is shown, click the Tools menu at the top of the menu bar, then select Options.
- From the Options window, click the Advanced panel.
- In the Advanced panel, click the Update tab.
- Under Firefox updates, select Never check for updates.
- Now click the OK button to apply the changes.
Please report back if this helped you.