We will try to support the latest version with security updates.
Please use any means to report a vulnerability, if you've found one.
You can open up an issue, or send me an e-mail via j62ce0o8h (at) relay.firefox.com.
I will try to answer as soon as possible, but no guarantees, sorry.
I can't promise any rewards, sorry :(. If the vulnerability is accepted, I will be happy to thank you in the project's README, but only if you wish, of course.
But still, please do reach out, I will appreciate it a lot.