In the past, to protect you from plugins that have stability or security issues, Firefox could only turn off the problematic plugin. Now Firefox can prevent the plugin from running automatically (which prevents many issues) and then let you choose to run or update the plugin. Here's how it works.

How click to activate works

1. When Firefox blocks a plugin you'll see a message similar to this:
   
   
2. You can then choose to run the plugin or update it (if an update is available).
   • If you click to activate the plugin, the missing content will load normally. However, the next time you visit the site or any other that uses that plugin you will see this message again.
     
     
   • If "Check for updates..." is available and you click it...
     
     
     • You will be taken to the Mozilla Plugin Check page where you will be shown links to update out-of-date plugins.
       
       

When is it OK to activate instead of updating a plugin?

Updating a plugin is always the safest thing to do but, sometimes, it may not be possible. For example, you may not be allowed to update a computer at work or school. In a situation like this, you can make a smart choice depending on your current task:

• If you're using a trusted site like YouTube or a special site for your work or school, you might feel safe enough to enable a vulnerable plugin in order to view the site’s content.
• If you don't fully trust a site that you arrived at from, for example, following a link, you probably do not want activate the plugin.

How to always activate a plugin for a trusted website

If you are unable to update a plugin and you are using a trusted site, you can set that plugin to automatically run whenever using that site:

Now, whenever you visit this site, the plugin will automatically run and you won't get the "Click to activate" message.