Thanks for the bug report :) The iconsdir attribute is set wrong in asciidoc. I updated a patch to set it correctly to '/usr/share/asciidoc/icons'[1].
Since this issue is not release critical it sadly won't be fixed in Debian bookworm. I will upload the fixed version after it released. In the meantime you could set the attribute iconsdir to '/usr/share/asciidoc/icons' to fix the warning. - Leon[1]: https://salsa.debian.org/debian/asciidoc/-/commit/42ed115af50ae6be20422d1574c966b27b4bce76
OpenPGP_signature
Description: OpenPGP digital signature
