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Zotero is a powerful, easy-to-use research tool that helps you gather, organize, and analyze sources and then share the results of your research. Use hardware acceleration. Hardware acceleration is when a browser uses a computer’s GPU to. The Flash plugin is blocked on some sites by default The Flash plugin can cause security, speed and stability problems on some sites. In order to give you a safe, fast and stable browsing experience, Firefox automatically blocks Flash on some websites that potentially cause problems.

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Mozilla's Firefox browser is known for its speed and a large collection of extensions that let you customize the experience to your heart's desire. But when Firefox is running slow, crashing, or not loading websites properly, it can be frustrating to figure out why. Follow our step-by-step guide to get your Firefox back to tip-top condition.

What are the most frequent problems with Firefox?

Overall, Firefox is a top-rated and highly reliable browser — good choice for both professional and everyday users. However, serving so many platforms on so many devices and screens, even the best of the best sometimes let us down. But worry not, in this how-to we've combined the most frequently occurring Firefox problems and written specific instructions on how to fix them.

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Why is Firefox so slow, hangs or keeps freezing?

Slow Firefox browsing experience is truthfully beyond annoying. It seems like it's almost working, but you can't get anything done.

Here we've listed some suggestions that should get your Firefox run faster.

1. Close inactive tabs

See how many tabs you have opened. More than a few? Active tabs mean active processes that take up your laptop's RAM and drastically slow down its capabilities. Just close the tabs you're not actively using. If they are important to remember, save them to bookmarks or stash them in a special 'Read Later' list in a to-do application such as 2Do.

2. Clear Firefox cookies and cache

All the websites you visit leave behind cached image files, which are supposed to speed up load times, and cookies, which can save you from having to log in over and over. Those are big conveniences if they work the way they're supposed to, but sometimes cache and cookies can cause glitches and slowdowns.

If Firefox is acting up, you can clear cookies and cache by doing the following:

Click the Library button
Choose History > Clear Recent History
Change the time range to Everything
Click the arrow next to the word Details
Select Cache and Cookies
Then click the Clear Now button

Alternatively, you can do this easier and safer with CleanMyMac. Just click Privacy in the sidebar and then choose Firefox from the list. Change the time range to Everything, and you can clear all of the cookies, browsing history, downloads history, tabs, saved passwords, and even autofill values.

3. Update Firefox and macOS

If closing tabs and clearing the cache didn't work, it's a good idea to update Firefox and macOS to its latest versions. When Firefox is active, just click on Firefox in the menu and select About Firefox. The latest available update should start downloading automatically. When it's ready, click Restart to Update Firefox and you are ready to go.

Updating macOS is easy too. Just launch the App Store on your Mac. Go to the Updates tab and wait till it shows you all the new software versions available. If you see new updates for macOS, click Update and follow the restart instructions.

4. See what consumes hardware resources

If the problem persists, check for high hardware resource usage. For basic information, you can use Mac's native Activity Monitor. However, to see the whole picture, get a pro-level app, such as iStat Menus. If you see Firefox using too much memory or CPU, you need to take some action.

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5. Troubleshoot plugins and extensions

When Firefox stops responding to your clicks it's very likely that one of your installed plugins is the culprit. To check for that, click the Menu button, and then choose Add-ons. In the Add-ons Manager's Plugins panel, you can select Never Activate for each plugin, then restart Firefox and see if the problem is still happening.

If the problem is gone, turn the plugins back on one by one, just changing that Never Activate option back to Always Activate. Restart Firefox each time and then try to recreate the error. Once the problem reappears, you'll know it was likely caused by the last plugin you re-enabled.

You can also remove a plugin with CleanMyMac's Extensions tab, which is actually a lot easier than using Firefox. In Firefox itself, you have to type about:plugins, then find the file path for that plugin and navigate to it in the Finder. Mozilla then recommends you change the filename to add an X in front, which will remove the plugin. You can reinstall a fresh copy of the plugin (from official sources only!), or just see if you can live without it.

To check your extensions in Firefox, go to about:add-ons, then click Extensions in the sidebar. You can disable extensions here, and then turn them back on one by one, in the same way you just checked your plugins. If you want to remove all your extensions and start fresh, you can click the Remove button or use the Extensions tab in CleanMyMac, which manages extensions, add-ons, and plugins from one place.

6. Stop loading Flash content

Preventing Flash content from loading automatically deserves a separate explanation. Some websites use way too much Flash content, and loading and playing all of that uses up your computer's resources, especially if you keep a lot of tabs open. Luckily, you can tell Firefox to stop loading Flash content by default, until you ask for it.

Click the Menu button and select Add-ons, or select Tools > Add-ons from your Mac's menu bar. (Or press Command-Shift-A, or type about:add-ons into the URL bar. It all takes you to the same place.)
In the Add-ons Manager, click Plugins in the sidebar, and then look for Shockwave Flash.
Change the dropdown from Always Activate to Ask to Activate. After that, websites will display an Activate Adobe Flash button in place of Flash content, and all you have to do is click that to allow Flash to display it.

Following the tips above should eliminate 90% of your Firefox problems. But if you're still experiencing troubles, there is more you can do. Read on.

Avoid Firefox crashing

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Mozilla Firefox crashes unexpectedly or won't open

Whether Firefox shows you an error message every time you try to launch the app or right when you're in the middle of a working session, there is only one way to fix that — reinstall the application.

The easiest way to reinstall Firefox is to quit it, delete the Firefox file from your Applications folder, and download the new version from the official Mozilla website. That will uninstall the application but keep all your user data intact, and when you reinstall a new copy, you bookmarks and passwords will still be there.

But that's not the best way to do it, since Firefox leaves all kinds of data on your hard drive besides the main application file. A better way is to use an application that's able to delete all Firefox information completely or simply reset the app, such as CleanMyMac.

Flash Plugin For Firefox

To reset the Firefox browser app on mac:

Launch CleanMyMac
Go to the Uninstaller tab
Choose Firefox from the list
Choose Application reset and click Uninstall round button

There are rare cases when the 'Firefox quit unexpectedly' message could be caused by the Mac security update. This happens when your Mac's firewall

Mac Plugins For Firefox