The mountdebugfs script is no longer provided by the blktrace package,
since a while back:

	blktrace (1.2.0-1) unstable; urgency=medium
	...
	  * Remove debugfs mounting init script, as systemd is moutning debugfs
	    by default nowadays (Closes: #873470, #705269)
	...
	 -- Bas Zoetekouw <bas@debian.org>  Sat, 19 May 2018 21:49:22 +0200

Bug #705269 provides some detail:

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=705269#10

An error:

	insserv: FATAL: service mountdebugfs has to be enabled to use service rasdaemon

is produced when the package is upgraded.

Therefore, another method to detect if debugfs is mounted is needed.
I came out with the initscript hack bellow, that informs the user and
also extends the script actions.  Is this an acceptable workaround?

You reported this bug against version 0.6.6-1, version 0.8.3-1 in Trixie
appears OK and version 0.8.4-1 in Testing also seems OK.

Can I close this?

  I've just taken both the 13.6 update package updates *and* rebooted to
a new, locally packaged, 6.18.38-based kernel.  On boot `rasdaemon`
failed to start from `/etc/init.d/rasdaemon` because of:

Jul 11 13:11:57 tuesday rasdaemon[2110]: rasdaemon: Can't locate a mounted debugfs

this being despite:

Jul 11 13:11:54 tuesday systemd[1]: Mounting sys-kernel-debug.mount - Kernel Debug File System...
Jul 11 13:11:54 tuesday systemd[1]: Mounted sys-kernel-debug.mount - Kernel Debug File System.

and indeed it is mounted.

  The cause of this is because I configured the kernel option
`TRACEFS_AUTOMOUNT_DEPRECATED` off.  There's an upstream issue about
this:

	<https://github.com/mchehab/rasdaemon/issues/227>

  There is also a PR, which got closed with a message "Merged, thanks!".
That code is at least in the `master` branch.

So, I guess either backport the fix, or at least document that currently
Debian expects that kernel config option to be 'Y'.  Not everyone will
be using Debian's own kernel images.