Thank you for your interest in our product.
Would you share more details about this issue? Does the browser start to record and crash at some point or it does not start to record at all?
Double check if the Firefox
extensions are installed and active. If it does not you may refer to this article
how to install them.
Some of the antivirus/firewall software is very aggressive. If you have one, try to stop it for a while and check if this is the case.
As a workaround you may record your tests in IE and execute them in Firefox or Chrome.