Easy Way to Repair Defaults?

I tend to create new files by forking existing ones.

This way, I don’t have to fix fonts, etc. for each new file… Until I am editing tables, and encounter unwanted “default” font settings I’ve never used.

Can I repair these “default” font settings, so the “default” font for the document matches the actual font in the document?

Can I repair these “default” font settings across multiple documents?

I switched from LibreOffice due to the strobing cursor, and when I use LibreOffice to open rtf files, it doesn’t display the fonts I’ve used for those files either.

Can I fix that?

There is no default font for a document, thus, it is not clear what you want to achieve. Try to rephrase.