noc-iceht-forth I can't find the newly created module position at file templateDetails.xml as described at the above documentation. Where did you add this?
I had added the newly created module position by entering the new position - after clicking on dropdown toggle in specific field as seen in screenshot
The said process is more seamless and quicker in terms of adding new module position which can be thereafter used globally for the specific template 🙂
The code for having new position can be seen in file"/tpls/blocks/masthead.php"
and also, the new position reflects inT3 framework > Layout
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