When viewing an issue on the website https://issues.guix.gnu.org/ the web interface allows you to post a comment, what more without authentication. Unfortunately, I am told by ropstat and podiki[m] on irc.libera.chat #guix that web comments don't actually work in their experience. If this option cannot be fixed in a timely fashion, it should not be offered at all. Otherwise, it only creates deep frustration in users, and maybe even lost comments depending on what client they use.
The same web interface also, correctly, invites users to instead send mail to <bug-number>@debbugs.gnu.org — however, the same helpful IRC users tell me that the mail is manually reviewed by a human moderator and may take up to a day to show up. This as such is perfectly fine, but does deserve mention as part of the same message on the web interface, otherwise it will once again create wrong expectations from users, frustration, messages sent multiple times, and more work for both users and moderators. PS: also, several of my attempts to post comments via the web form failed with an unhelpful error message when posting "There was an error submitting your comment!". At some point I conjectured that it was due to my using an accent in my name "Faré", but one of my attempts with that name did end up with "Your comment has been submitted!". This is moot considering the above issue, but may become important if the resolution is to fix web comments.