No problem. I contacted them at support@protonme.zendesk.com, and they answered very quickly(a couple of hours):
"Hello,
Thank you for reaching out.
Please note that we typically add the open-source code repository a few weeks after releasing a product, so it should be available soon.
You can keep an eye on it here: https://proton.me/community/open-source
Thank you for your patience.
If you have any other questions or concerns, feel free to let us know.
Kind regards,
Nikola L.
Customer Support
Proton Mail"
So, let’s wait
