Hello,
Thank you for contacting Rank Math today.
That is is the default set example for the filename variable, it is usually displayed if there is no actual filename to display for the variable. There is no file in your post/page description so %filename% is going to display that as a default.
Hope that helps. If you have any further question(s), please let us know. Thank you.
Hello,
We are are glad we could help.
If you don’t mind me asking, could you please leave us a review (if you haven’t already) on https://wordpress.org/support/plugin/seo-by-rank-math/reviews/#new-post about your overall experience with Rank Math? We appreciate your time and patience.
If you do have another question in the future, please feel free to create a new forum topic, and it will be our pleasure to assist you again.
Thank you.