Version 0.4.43+ds-2 of mdbook is marked for autoremoval from testing on Tue 11 Mar 2025. It depends (transitively) on rust-axum, affected by #1093933. You should try to prevent the removal by fixing these RC bugs.
Migration status for mdbook (0.4.43+ds-2 to 0.4.43+ds-3): Waiting for test results or another package, or too young (no action required now - check later)