Three years ago, I made the conscious decision to switch to Mozilla’s Firefox. With Firefox, I’ve noticed a significant improvement in my PC’s overall and browsing performance. Except for one minor hiccup, it would have been the ideal browser.
I’m not sure which is more annoying: the yellow warning message or the fact that you were in the middle of a website and may have to restart? Yes. We’ve all been there, maybe more than once. In fact, according to the latest report, 4.38 percent of all reported browser crashes in the last 7 days were caused by a website hanging up the browser.
Do not despair, as there are a few tried and tested methods to fix this problem.
Table of Contents
How to Fix “a Web Page Is Slowing Down Your Browser” in Firefox

Below listed are some of the methods that have proven useful to get rid of the annoying yellow banner in the Firefox browser.
Delete Cookies and Cache
- Go to the URL bar. Type the following
about:preferences#privacy
and press Enter. - This will bring up the Privacy & Security options of your browser. Scroll down to the Cookies and Site Data section.
- Click on the Clear Data button to bring up the Clear Data dialog box.
- Click Clear to confirm you want to clear all cookies and cache.
- Restart your browser.
Disable Add Ons
- Go to the URL bar. Type the following about:performance and press Enter.
- This will bring up the built-in Task Manager in Firefox with a list of all running tabs and add ons.
- Looking at the Energy Impact and Memory Data should give you a good idea of which add on is affecting your browser. Select the add on that you’d like to disable.
- At the end of the row to the left of Memory data, click on the displayed button to open the add on in Add on Manager.
- Use the toggle button on the add on page to disable the add on.
Installing the Latest Version of Browser
- Go to the URL bar. Type the following about:preferences#general and press Enter.
- This will bring up the General options of your browser. Scroll down to the Firefox Updates section.
- Click on Check for updates and make sure you have the latest version.
- Click on Automatically install updates. This makes sure all the browser never misses an update in the future.
Updating Graphics Card Driver
- Go to the Start Menu. Type the following Device Manager and press Enter.
- This will bring up the Device Manager Window with a list of all devices. Under Display adapters, find your Graphics Card along with the manufacturer name.
- Do a Right Click and Select Update Driver to bring up the update wizard window.
- Click on Search Automatically to find the latest driver update and install it.
Disable Tracking
- Go to the URL bar. Type the following about:preferences#privacy and press Enter.
- This will bring up the Browser Privacy section. Go to the Enhanced Tracking Protection section(usually at the top of this page).
- Among the provided options, click on Custom. Make sure that all checkboxes are checked as shown below.
- In Tracking content options, use the picklist to select ‘In all windows’. This ensures a browser-wide protection.
- Restart the browser to apply changes.
Using Advanced Settings Options
- Go to the URL bar. Type the following about:config and press Enter.
- This will bring up the advanced configuration settings of your browser. Click on Accept the Risk and Continue.
- In the displayed search bar, type the following : processHang.
- You should see two matched options being displayed with their values set to true.
- Double click on the value to toggle it to false. Repeat this for both options.
- Restart the browser to apply changes.
Disable Javascript
- Use Steps 1-3 described in Approach #6 to bring up Advanced Settings options.
- In the search bar, type the following : javascript.enabled.
- Double click on the value to set it to false.
- Restart the browser to apply changes.
This will solve any javascript-related crashes slowing down the browser. But one thing to note here is that most modern websites need javascript to work correctly. Turning this setting off could lead to other websites not displaying properly. If that is the case, it is recommended to keep the setting enabled.
Using TroubleShoot Mode/Safe Mode

- Click on the Hamburger icon in your browser to open up the menu.
- Click on Help options and Click on Open in TroubleShoot Mode. Older versions may have Safe Mode instead.
- Hit the Restart button
Note that, safe mode isn’t technically a ‘fix’ for the web page slowing down the issue. It simply allows you to use Firefox with extensions and customizations turned off. So, you would be able to open the website you wanted in safe mode if anything was causing trouble in normal mode. See this article here for more information about the troubleshooting mode.
After trying all the steps above, hopefully, you have everything just as you wanted, and that annoying yellow error bar won’t trouble you for good anymore. If sadly, you still get the same error, a total uninstall and reinstall after syncing your settings and bookmarks to your Firefox account is the final option left.