update comment

Author: lcnr

compiler/rustc_type_ir/src/ty_kind.rs

@@ -92,10 +92,10 @@ impl<I: Interner> AliasTyKind<I> {
 /// with `IsRigid::Yes`. At this point we no longer have to try and renormalize this alias
 /// later on.
 ///
-/// Alias handling is currently still in flux for the new trait solver and this is currently
-/// somewhat messy. Please reach out on #t-types/trait-system-refactor-initiative if you encounter
-/// this and it isn't immediately clear what to do. See https://hackmd.io/@lcnr/SyjTAeixzg for
-/// a quite terse writeup of what's going on here.
+/// FIXME(#155345): Alias handling is currently still in flux for the new trait
+/// solver and this is currently somewhat messy. Please reach out on
+/// #t-types/trait-system-refactor-initiative if you encounter this and it isn't
+/// immediately clear what to do.
 #[derive(Debug, Clone, Copy, Hash, PartialEq)]
 #[derive(TypeVisitable_Generic, GenericTypeVisitable, TypeFoldable_Generic)]
 #[cfg_attr(