This is for version 5.6.2, which is not an available alternative. GnuPG key BF8806F188590D8F includes a user ID containing an HTTPS URL. When looking at a mail signed by that key, KMail complains that it is a scam, citing: This email contains a link (mailto:https://censored,address@censored,address@censored,https://censored) which contains multiple http://. This is often the case in scam emails. Scam detection should only operate on the text of the e-mail itself, not locally generated GnuPG output.
Thank you for reporting this issue in KDE software. As it has been a while since this issue was reported, can we please ask you to see if you can reproduce the issue with a recent software version? If you can reproduce the issue, please change the status to "REPORTED" when replying. Thank you!
I checked on KMail 5.21.3, and can no longer reproduce this problem.