To facilitate the massive adoption of crypto will be necessary to have a better UX allowing the users to interact with crypto currencies natively from the browser. This would allow seamless integrations and not making necessary to install plugins like Metamask. Opera is supporting the web3 extensions supporting Bitcoin, Ethereum, ERC20 tokens, etc. The usage of Opera makes easier to make and receive payments and giving to the final user more security about the transactions made. https://www.opera.com/crypto What are the plans of Mozilla/Firefox about this?