Interaction of slurs and bar checks

Hi all,
I'm posting to bug-lilypond instead of opening an issue in the tracker,
because
I'm not sure if the behaviour is somehow intended or a bug.
Consider the following example:

\version "2.24.0"
{
   \time 2/4
   d''8 r e''4 |
   ( cis''16 ) cis'' d'' d''
}

It gives a warning "Unattached SlurEvent" and does not print a slur.

Removing the bar check gives the correct rendition.

What also works is:

\version "2.24.0"
{
   \time 2/4
   d''8 r e''4 ( |
   cis''16 ) cis'' d'' d''
}

i.e. moving the opening parenthesis before the bar check.

This behaviour is not new, 2.20.0 behaves exactly the same.
At least NR 1.2.5 does not mention such a kind of interaction.
Am I missing something?

Michael