Ability to manipulate the %filename% placeholder to either show or not show the filename extension

[pcanham]

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When i am creating a drawing i add a header into each file showing the Filename, Author and date last modified/saved. It would be nice if we could either manipulate the %filename% placeholder so we can turn off the filename extension e.g. .drawio

Describe the solution you'd like
Could we either have another placeholder created which doesn't show the file extension

Describe alternatives you've considered
Ability to perform some basic manipulation functions such as trim function within the placeholder to remove the file extension