We're happy to help!
We have lots of information available in our documentation that might help you with your issue.
We may already be on the case! We list known bugs & quirks on our Known Issues Trello board.
We track security concerns through BugCrowd. Please submit security problems there. We hugely appreciate that. Plus this way you get public credit for your work.
We prefer you use the form, because it helps us know a bit more about you and your account. But if that form isn't working or you really prefer email, you can reach us at firstname.lastname@example.org