To make your browsing experience faster, your web browser downloads the resources needed to display webpages, such as images, JavaScript files, and style sheets, into the browser’s cache. When you visit a webpage again, the browser uses the downloaded resources to display the page instead of downloading them again.

RELATED: Why Is My Browser Storing So Much Private Data?

However, the browser’s cache is useful for more than just loading webpages faster. If you’re in a location with unreliable internet connectivity, or none at all, you can use your browser’s cache to access copies of websites you’ve already visited when you were online. So, if you know you’re going to be without a reliable internet connection, be sure to visit the websites you want offline access to before then, so they are stored in the cache for viewing when you’re offline. Then you can use Firefox’s “Offline Mode” to view them.

There are two ways to browse offline in Firefox. The first method uses the menu bar, which is now hidden by default in Firefox. To temporarily show the menu bar, press “Alt” on your keyboard. The menu displays long enough for you to select a command and then hides again. If you want the menu bar to display all the time, right-click on the an empty area on the tab bar and select “Menu Bar” from the popup menu.

To turn on Offline Mode using the menu bar, select “Work Offline” from the “File” menu in the menu bar.

A check mark displays to the left of the Work Offline option to indicate it’s enabled.

The second method of enabling the Offline Mode in Firefox is in the Developer menu. Click the main Firefox menu by clicking the button with three horizontal bars on the toolbar. Then, click “Developer” on the drop-down menu.

On the Developer menu, click “Work Offline” at the bottom.

NOTE: The Work Offline option on the menu bar and on the Developer menu are the same option. Turning the option on or off in one place will do the same thing automatically in the other.

If your computer is offline and you have not enabled Offline Mode in Firefox, The Server not found screen displays when you try to go to any webpage. To solve this, enable Offline Mode and go to the webpage you want to visit again.

The copy of the webpage that’s stored in the cache displays (if you visited the webpage previously, while online), rather than downloading it from the website’s server. Any dynamic parts of the webpage, such as advertisements or streaming video, are not displayed, and any updates made since your last visit will not appear.

When you are offline and Offline Mode is on, and you try to access a webpage you have not visited while online (the webpage is not stored in the cache), the following screen displays. You will have to visit the webpage when you’re online again to store it in the cache for offline viewing.

Once you’re online again, be sure to turn off the Offline Mode option so you can browse webpages normally.

Remember, when you access a cached copy of a webpage, you are viewing an old version of that webpage. You can use Firefox’s offline mode to view any website offline, but it’s probably more useful for websites that don’t update that often, so the cached copy is not quite so out of date.

RELATED: How to Clear Your Browsing History in Firefox

If you clear your cache, you’ll have to visit the websites you want offline access to while you have an internet connection, so those websites are stored in your cache again and available when you do not have an internet connection. Not clearing your cache in Firefox is also a way to speed up your browsing experience.

If you also use Chrome, you’ll be glad to know that it has an offline mode, as well.

Profile Photo for Lori Kaufman Lori Kaufman
Lori Kaufman is a technology expert with 25 years of experience. She's been a senior technical writer, worked as a programmer, and has even run her own multi-location business.
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