I use whitespace-mode and my own highlighter for HACK/FIX/REFACTOR/etc tags and they're drowned out by your mode's highlighting. You can occasionally see blank-mode flickering and then getting overwritten.
I don't know modes/faces well enough to debug this.
This should work out of the box with 24... possibly 23 as well. Make a ruby file with a long line or mix in tabs and you should see extra highlighting with normal ruby mode but not on ERM.
I use whitespace-mode and my own highlighter for HACK/FIX/REFACTOR/etc tags and they're drowned out by your mode's highlighting. You can occasionally see blank-mode flickering and then getting overwritten.
I don't know modes/faces well enough to debug this.
My whitespace (customize) setup:
This should work out of the box with 24... possibly 23 as well. Make a ruby file with a long line or mix in tabs and you should see extra highlighting with normal ruby mode but not on ERM.