I know how to find and validate email addresses (usually it's as simple as firstname.lastname@example.org). During interviews, I usually have previous email contact with the "primary" interviewer, but I go through many interviewers, whom I know the name but not the email. Usually, I do not ask for the email address, but I always send a thank you email to each of the interviewers. Is this appropriate or would this be awkward and harmful to my interests? Should I always ask for the email address? I feel as if that may be awkward to ask, especially for some of the technical interviewers. Also, sometimes I forget to ask.
Does it change anything that I am applying for cybersecurity related positions?