I’m not the best with Notepad++ and don’t use it for coding, so hopefully I don’t sound too inept. I’m using it for a writing project where the line maximum needs to be 78 characters.

I tried using the Vertical Edge Settings option under Preferences > Margins/Border/Edge, but setting it to 78 produces:
Imgur Pic, 78 VES

Whereas setting it to 97 produces the intended result:
Imgur Pic, 97 VES

It might be important to note that I do have a user defined language for this writing project that just highlights the specific syntax used. I didn’t write the language and received it from someone else.

However, when I switch from the user defined language to markdown (preinstalled), having the Vertical Edge Setting to 78 works as intended:
Imgur Pic, w/ Markdown Enabled