hilarious behaviour of --include-dir command for clamscan

[MarkyMarkDE]

this is hilarious, why this won't work?

		/usr/bin/clamscan
		     --include-dir="^/home/$SUDO_USER/.thunderbird/Marc/Mail/"
			--recursive="yes" 
			--quiet 
			--infected 
			--alert-broken-media="no" 
			--database="/var/lib/clamav" 
			--log="/var/log/clamav/clamscan.log"
			#--move="/etc/clamav/virusevent.d/Mail"

this should scan only the included path recursive

But when i do this:

		/usr/bin/clamscan 
			"/home/$SUDO_USER/.thunderbird/Marc/Mail/"
			--recursive="yes" 
			--quiet
			--infected
			--alert-broken-media="no"
			--database="/var/lib/clamav"
			--log="/var/log/clamav/clamscan.log"
			#--move="/etc/clamav/virusevent.d/Mail"

OR this - here i want to scan only two folders in path

               /usr/bin/clamscan 
		        --include="^/home/$SUDO_USER/.thunderbird/Marc/extensions/"
                        --include="^/home/$SUDO_USER/.thunderbird/Marc/Mail/"
		        --recursive="yes" 
		        --quiet
		        --infected
		        --alert-broken-media="no"
		        --database="/var/lib/clamav"
		        --log="/var/log/clamav/clamscan.log"
		        #--move="/etc/clamav/virusevent.d/Mail"

it worked well.

Can someone explain what's the reason for this?
Why does --include-dir="PATH" not working similar then without it, as you can see the path to maildir is in both cases absolutely identically.

When i run clamscan with the include-dir command, it scanned a few seconds and results in "no viruses found scanned folders 0" but in this PATH many folders included.

Oh and the var SUDO_USER expanded to the whoami.
My complete ClamAV runs with cronjob for sudo only.

Im Running on Ubuntu 22.04.1 with ClamAV 0.103.6 (26811), no newer version available at present.

regards,
Marc