Error during GRUB cleanup: `ValueError: embedded null byte`

[hololeap]

I'm not sure if this is a problem with my system and/or user error. Here is the output:

# eclean-kernel --destructive --num 3 --sort-order mtime --debug
...
DEBUG:root:/boot/grub/grub.cfg found
DEBUG:root:Bootloader: <ecleankernel.bootloader.grub2.GRUB2 object at 0x7ff34b287cb0>
DEBUG:root:in get_removal_list()
Legend:
[-] file being removed
[x] file does not exist (anymore)
[+] file being kept (used by other kernels)

* Removing kernel other 6.18.35-gentoo-dist-bin (unwanted)
Traceback (most recent call last):
  File "/usr/lib/python-exec/python3.14/eclean-kernel", line 8, in <module>
    sys.exit(setuptools_main())
             ~~~~~~~~~~~~~~~^^
  File "/usr/lib/python3.14/site-packages/ecleankernel/__main__.py", line 391, in setuptools_main
    sys.exit(main(sys.argv[1:]))
             ~~~~^^^^^^^^^^^^^^
  File "/usr/lib/python3.14/site-packages/ecleankernel/__main__.py", line 341, in main
    p = subprocess.Popen(scmd)
  File "/usr/lib/python3.14/subprocess.py", line 1039, in __init__
    self._execute_child(args, executable, preexec_fn, close_fds,
    ~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
                        pass_fds, cwd, env,
                        ^^^^^^^^^^^^^^^^^^^
    ...<5 lines>...
                        gid, gids, uid, umask,
                        ^^^^^^^^^^^^^^^^^^^^^^
                        start_new_session, process_group)
                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.14/subprocess.py", line 1920, in _execute_child
    self.pid = _fork_exec(
               ~~~~~~~~~~^
            args, executable_list,
            ^^^^^^^^^^^^^^^^^^^^^^
    ...<6 lines>...
            process_group, gid, gids, uid, umask,
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
            preexec_fn)
            ^^^^^^^^^^^
ValueError: embedded null byte

Full log and a smattering of other relevant info here: https://gist.github.com/hololeap/33b51569821f9e367fe596d481b7e49c