Hi, a portable version is available from https://portableapps.com/apps/internet/firefox_portable which is considered to be a well respected site. Firefox portable isn't available directly from Mozilla.

If your question is resolved by this or another answer, please help other users by marking the best reply as Solved. Thank you!

Hi, a portable version is available from https://portableapps.com/apps/internet/firefox_portable which is considered to be a well respected site.

I know. And also surprised. Why some incomprehensible people, not having access to the source file, were able to make a portable version, but the developer himself cannot. Of course, I will not use the program in which incomprehensible people were digging. Thank!