My account activation mail went to the Spam and was marked suspicious. When I opened the message, Gmail displayed a header box on an orange background:
Be careful with this message
Gmail could not verify that it actually came from gbadev.net. Avoid clicking links, downloading attachments, or replying with personal information.
"Show original" in Gmail said SPF failed and DMARC failed.
(I created this in the wrong area. Could a moderator move it to site feedback?)