RE: [External] : Re: Can watermarking Unicode text using invisible differences sneak through Emacs, or can Emacs detect it?

[Drew Adams]

> > I've remembered a question on emacs.stackexchange.com about
> > customizing the glyphless char display, and doing so on a
> > per-mode basis; so just in case this is useful to anyone:
> > https://emacs.stackexchange.com/a/65109
> 
> Last time a similar discussion came around (that time about
> direction-change Unicode characters in source code used for malicious
> purposes) white-space-mode was mentioned as a place where to put
> visualization of "such things".
> 
> This time it seems even more appropriate.

Yes, `whitespace-mode` can help, but it's
somewhat limited wrt highlighting different
characters (or sets or ranges of characters)
differently.

My library `highlight-chars.el` can help
more with this kind of thing.

code:
https://www.emacswiki.org/emacs/download/highlight-chars.el

Description:
https://www.emacswiki.org/emacs/ShowWhiteSpace#HighlightChars