I launched Mailmask (<a href="https://msk.sh" rel="nofollow">https://msk.sh</a>) recently, trying to solve the same problem. Welcome to the club!
Many sites I've tried to register on have rejected my attempts to sign up using services similar to yours.<p>Do you have any plans to address this issue somehow?
The site doesn't load at all without JS.<p>Maybe something simple in a <noscript> tag would help accessibility for those of us who don't enable JS on every site by default?