How to disable multiple firefox process running issue?

Hello everyone.How are you? I am suffering from an issue with Firefox on Ubuntu 20.04 PC. That is, multiple Firefox processes running in the background. When I work on the computer, a lot of internet bandwidth is wasted. Guys, I don’t know why these processes are running in Firefox and how to fix this issue. Because after several attempts with the help of this article failed to solve the issue! Can anyone help me to solve this issue? Any suggestions will be appreciated.