That said, I'm seeing enterprise security companies selling soft forks of Chrome with all sorts of inspection and policy built in. Basically, instead of doing DLP/URL filtering/risk management on a MITM box, they're pushing it to the browser. This helps remove the need for TLS decryption, and the need to funnel their browser traffic to any particular tunnel endpoint.
I guess what I'm saying is... Firefox might want to take a look at what those companies are doing to Chrome and figure if there is a way to make it easy to plug that kind of security into their browser.
edit: just noticed this is a paid service. So I triple down on what I said. Companies that are "buying" browsers are buying browsers with deep inspection and security features baked in. I don't know if they'll buy support for FF when Edge is free.