This extension is syntax highlighter for troff (groff, nroff) U**x document formatting system language.
Search for TROFF Syntax from the extension installer within VSCode or execute below line in the command palette (F1/Ctrl+Shift+P):
ext install ban.troff
Please report all the errors and/or annoyances that you see on the issues page.
Adapted & fine-tuned to Visual Studio Code from Sublime Text extension by McFuzzypants.