Redirect error after a comment deletion

After deleting one of my own (obsolete) comment I was redirected to the comments’ page but on the unencrypted URL (HTTP instead of HTTPS) which seems to trigger a browser error.

Hmm, never encountered this when deleting before, and not sure how to troubleshoot it. Which film page was it?

It was on Mongjeongae (2011) - iCheckMovies.com the first time but I reproduced it on every comment I wanted to delete.

I just reproduced it on Jogeumman Deo Gakkai (2010)'s comments - iCheckMovies.com and here is my screenshot (Firefox 103):

And here is a HAR dump of the network exchange: Upload files for free - www.icheckmovies.com_Archive [23-05-10 16-57-21]_redacted.har - ufile.io
(redacted to remove some sensitive context like my session ids and such)

I suppose because the POST is a redirect (302 Found) to:
http://www.icheckmovies.com/movies/jogeumman+deo+gakkai/comments/
which in turn is a permanent redirect (301) to:
https://www.icheckmovies.com/movies/jogeumman+deo+gakkai/comments/

The POST probably shouldn’t redirect to an http (without TLS) path. Our session cookie has a Secure flag and is only valid in an HTTPS context. I’m not sure that is the root cause of the problem though.

Thanks! That’s beyond my tech knowledge.

@Marijn this may be useful for you.