How to Fix: High CPU Usage with Firefox browser?

Vishnu

Here’s how to fix the high CPU usage issue caused by Firefox browser.

How do you know that Firefox is using High CPU?

When the Firefox browser starts loading very slowly or freezes in between the browsing activities, it is a sign that the browser is using more memory than it should. It can be noticed when we open several tabs or even windows in the browser.

Sometimes you may also notice on the task manager that Firefox is using a lot more CPU resources than it should on average.

Below is a list of troubleshooting options available that can help fix the problem and start enjoying the speed the browser offers at its optimum.

Boot Firefox to Safe Mode

  • Launch the Mozilla Firefox Browser
  • Click on the hamburger lines in the top right corner of the browser.
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Use Strict Tracking Protection

  • Launch the Firefox browser on your device
  • Click on the three hamburger lines in the top right corner of the browser.
  • Scroll down to the “settings” option and click on it to open the settings page.
  • Tap on the “Privacy and Security” section from the left side of the page.
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  • Under the “Enhanced Tracking Protection”, scroll down and select the “Strict” mode option.

That’s it. Go back and check if there are any changes now.

The strict mode is prone to render many websites less functional, but if it solves the problem, we might not have an option here for the loss of configuration we had taken time to set.

Disable or Uninstall Suspicious Plugins, Themes, and Extensions

  • Launch Firefox and click on the hamburger lines in the top right corner of the browser.
  • Scroll down and click on “Add-ons and themes”.
  • You will be directed to the extensions section.
  • Under “Manage your extensions”, scroll the installed extensions and toggle to deactivate all those you deem unnecessary.
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  • Next, head over to the Theme section. If you already have many themes installed, look for the system theme and activate it by clicking on the “enable” button.
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  • Finally, on the same page, head over to the “plugin” section. Here, we have the option to never allow activating forever.
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Enable Hardware Acceleration

  • Launch the Firefox browser
  • Click on the three hamburger lines in the top right corner of the browser.
  • Make sure you are on the General tab, then scroll down to the “Performance” section.
  • Uncheck the box for “Use recommended performance settings”.
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Below the performance settings, make sure the “Use hardware acceleration when available” box stays marked.

Update or Reinstall Your Graphics Card Drivers

The graphics card is used to heavy lift heavy processes on the browser like games. Keeping up-to-date is one of the most crucial things in order for Firefox to run smoothly.

To update the Graphics Card drivers:

  • Open the Run command by pressing the Win + R command keys
  • Type in “devmgmt.msc” and hit ENTER.
  • The Device Manager settings will then be opened.
  • Click on the Display adapters to expand the menu.
  • Right-click on the Graphics card driver installed on the device
  • Tap on “Update driver” and follow the steps to automatically update the drive.
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  • Finally, restart the system, and check to see if the issue has been resolved.

If the problem still persists:

  • Click on the “Uninstall device” option
  • Confirm the actions, and head over to the respective Graphics card homepage.
  • There is a form to manually find the matching driver for that particular deviceto enter the particulars. Just enter the information in the required field.
  • Download the latest driver and go on and install it.

Delete the “content-prefs.sqlite” file.

  • Launch the Mozilla Firefox browser.
  • Click on the hamburger lines in the top right corner of the browser.
  • Scroll down to the “Help” section and tap on it
  • You will be directed to another menu, navigate to the “More troubleshooting information” option and click on it.
  • On the Application Basic section, look for “profile directory” and click on the “Open Directory” button.
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Select the “content-prefs.sqlite” file and delete it from the folder.

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Now restart the Firefox browser, and you are done.

Run Firefox in Troubleshoot Mode

The troubleshooting mode disables extensions, themes, and all the custom settings you had in place.

  • Launch the Firefox Browser
  • Click on “Help” and select “Troubleshoot mode..”
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  • Now click onthe Restart button.
  • Next, click on Open when the Firefox browser asks for confirmation.

Refresh Firefox Browser

  • Launch the Mozilla Firefox browser.
  • Click on the hamburger lines in the top right corner of the browser.
  • Scroll down to the “Help” section and tap on it.
  • You will be directed to another menu, navigate to the “More troubleshooting information” option and click on it.

To avoid going through the above steps, you can paste the “about:support” on the Firefox address, and hit ENTER.
Click on the “Refresh Firefox” button on the top part of the page. You will get a confirmation pop-up window to confirm the action.

When the process is done, just reopen the Firefox browser.

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This process will delete all the extensions and restore all the previous configurations you had put in place to default.

Scan the system for Malware

Malware is a malicious program that hinders CPU performance to a great extent. The best option is to run a full scan on your system. Trojans and worms are known to increase the consumption of the CPU.

It is recommended to run a virus and malware scan in order to determine if they might have been installed on the system without your knowledge. This is also because some malware disguises themselves as normal programs with the actual names of some useful programs. Only searching with an eye might not be enough in some scenarios.

The antivirus should also be up-to-date, so it can be able to detect the latest viruses that might have previously sneaked into the system undetected.

Find Specific Guidance Online

High CPU usage can be caused by a variety of reasons, and thus there might not be one solution that can solve the issue once and for all. Go to the task manager and identify the program or the processes that cause this particular issue in your system.

With the multitude of users in the modern era, it has become a bit difficult to encounter an issue that has not been identified before in online forums. Googling the issue specifically can lead you to solutions that have been proven to work, or that help ease the issue of CPU usage. Just make sure to include as much detail as possible, not excluding the hardware you are operating in. 

Close the Firefox running in the background

Sometimes when we close the Firefox browser, it might remain running in the background, and we think it is already closed. To confirm that it is fully closed:

  • Launch the task manager by clicking on the Ctrl+Shift+Esc key combinations
  • Under the Background processes, head over to the “processes” tab
  • Scroll to see if there is any Firefox activity running there
  • If you find them, right-click on them and click on “End Process”.
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This will definitely put a stop to all processes concerning the Firefox browser.

Reinstall the Firefox Browser

Reinstalling should be one of the last options you can consider when you have tried all the other options. This will reinstall everything fresh and all the files will now not have any corrupted ones that might have been causing the high CPU usage.

To do so:

  • Open the “Run” command by pressing the Windows + R key at the same time.
  • Type in “appwiz.cpl”, without the quotes, to open the “Application and feature”.
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  • Double-click on Mozilla Firefox, and a small “Uninstall” window will pop up.
  • Click on it, and the Firefox browser will now start uninstalling.
  • When the installation is finished, head over to the Firefox download page, and download the latest software.
  • Follow the instructions to install it and a new Firefox will now be installed in the system.

Conclusion

It might be ideal to restart the system every time we encounter some mishaps on our system. But, if we go on doing the same thing as opening too many tabs in a session, the same problem will continue to persist and hinder our workflow. Opening a few tabs will help to reduce the load on the system memory usage.

You can even go to the extent of closing other apps running simultaneously and letting Firefox be the only application active when you are doing intensive tasks online.

Another solution is to increase the size of the RAM, so it can be able to handle some tasks and improve the system’s performance. Not to forget, Firefox should also be kept up-to-date at all times.

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