A somewhat niche one (again).
I use a template in LibreOffice’s Writer program, so that I have styles etc. set up to my liking.
It is the default template, meaning that, when I create a new document in Writer, it automatically uses this template.
It works well - other than when I export the file to PDF (whether directly, or using the more involved dialogue). Rather than using the document’s name as the PDF’s title, it uses the name of the template (in my case, “decoded.legal basic”.)
Not the end of the world, but not ideal.
There’s a solution!
In LibreOffice Writer, I went to File / Templates / Manage Templates, to open the Template Manager.
In Template Manager, I right-clicked on the template I wanted to edit, and selected “Edit”.
That opened up my template in a Writer window.
I went to File / Properties / Description, and deleted the template name from the Title field. I saved the template.
And now, when I export a document to PDF, it uses the document’s filename as the PDF title.