@PeterJones Again many thanks for your effort and patience. I will try to work out your line of thought, but that will not be today, perhaps not even tomorrow. Busy as hell and in the mean time I work as I have done two years or so, which is rather a nuisance.
But again I appreciate your helpful thinking.
I will be back as soon as I can.
Cheers.
Is it possible to apply a visual design like this for Notepad ++? Why?
No. You cannot affect the styling of the GUI itself in that manner.
You can affect the text and background colors, so you can make light text on dark background: there are plenty of builtin “dark” themes that ship with Notepad++, or you can design your own theme to your liking. There is documentation on themes and the Preferences > Style Configurator dialog.
So I see a conflict: do you want to use a UDL ([Language > Define Your Language](https://npp-user-manual.org/docs/user-
If using the builtin HTML lexer, unfortunately Settings > Style Configurator > HTML dialog doesn’t seem to list any styles that have user-defined keywords. And even if you could, I think comments would override that.
I was hoping to simply modify the built in HTML lexer. Thanks for confirming that that is not possible.
However, there are workarounds:
you can add extra highlighting to a builtin lexer (like the HTML lexer) using regexes via the script EnhanceAnyBuiltinLexer.py that @Ekopalypse shares, in this linked post
you can add extra highlighting to a UDL language using regexes via the script EnhanceUDLLexer.py that @Ekopalypse shares in this linked post
I will check these out, but regex is usually challenging for me. I’ll give it a go.
Some language/style combinations (like Preferences > Style Configurator > Perl > INSTRUCTION WORD) will additionally have a list of default keywords (not editable) and user-defined keywords (which allow you to add new keywords to apply this style to).
Authentication errors in Notepad++ sound like a proxy issue. See this topic for how to set up Notepad++ to properly see your proxy. Unfortunately, there are some proxy configurations that NPP doesn’t handle. You may have to turn off the auto-updater, and manually install updates and maybe plugins as well.