HTML\CSS\Javascript etc languages - coloured highlighting

is there a way to view HTML/CSS/Javascript files (and other languages) with coloured coding, so they show with reserved keywords etc in colour? this would be very useful in the viewer pane.
If not, can this be added please

Any viewer that does that and works in File Explorer's preview pane should also work in Opus's preview pane.

One I know of is the one that's part of Microsoft PowerToys, but it unfortunately causes so many problems I would not recommend it (so many, in fact, that we block it by default if it's installed). Unless it has improved since I last looked at it, at least.

There are some older Opus-specific viewers written by people here on the forum which do similar, but I don't think any of them have been maintained over the years.

At some point, we may write our own, as an update to the stock text viewer, but there's other work that needs doing first.