mb_strlen(): Argument #2 ($encoding) must be a valid encoding, "auto" given

[mcbmcb0]

Hi
with php 8.2.4 (on debian 11) i get this error:
mb_strlen(): Argument #2 ($encoding) must be a valid encoding, "auto" given
I thought 'auto' was a valid value, but maybe not with php 8.2
if i add if($encoding == 'auto') $encoding = null; then all works, tho I'm not sure if null is valid <php8.0

...and ...
Deprecated: basename(): Passing null to parameter #1 ($path) of type string is deprecated in ...\docx2md.php on line 289
hacky fix by: basename($mdFilename ??"", '.md')
I assume these are php 8.2 changes

thanks for your work!

[u01jmg3]

Fancy putting a PR together?