You may be also interested in this: Windows 10 V1903 KB4512941 Update Causes 100% CPU Core Usage You can try updating graphics drivers to solve the problem.

Graphics Drivers: The Firefox using too much CPU issue often is related to graphics and the graphics drivers installed on computer.

Suspicious add-ons on Firefox: If you have installed any new add-ons recently, you ought to consider removing them to see if they are the root causes of the error.

Issues with the current configuration files: If some issues start happening to the present Firefox configuration file, it’s time to delete the file and create a new one to fix the error.

Here are some factors that may trigger the error and you can take them as your reference. The best way is to find the exact reason for the error and carry out the corresponding operation. To solve Firefox using too much memory, you need to find the possible causes of it. What Causes the Firefox Using Too Much Memory Error

Fix 4: Check for Flash Hardware Acceleration Disable Specific Plugins.

Fix 2: Disable Resource - Consuming Extensions and Themes.

Fix 1: Delete the Current Firefox Configuration File and Create a New One.What Causes the Firefox Using Too Much Memory Error.

Now, let’s begin exploring them together. Do you know what causes this error? How to fix this? You will get the answers from this post of MiniTool.

If you often use Firefox, you may be familiar with Firefox using too much memory error.

Firefox flash plugin corrupted