Then I think I misunderstood what jasode was asking. Specifically, the example (our link) already names groups if you hover over matching text (group #1, etc) - I thought they were just asking for the highlight color to correspond to the group # listed.
Thanks for mentioning the tooltip popups. I didn't realize RegExr used mouseover/hover events on the matching text since the other regex sites don't do that. (It seems like non-obvious UX/UI but I now notice that the bottom left corner does say "Roll over a match or expression for details" -- but who reads the instructions?!?! Nobody's got time fo 'dat.)
Nevertheless, I prefer explicit color-coding highlighting the boundaries instead tooltips displaying the offset numbers.
Interesting, somehow I just instinctively moused over the text when I first visited the page. Another example of the subjectivity of UX and need for UI to be explicit and versatile I guess.
yes, I only knew about the hovering because of the instructions, which I did read. FWIW, my reaction was it would probably be better if they were all visible at once, who has time to hover over stuff.
anyway since they have the logic to already know what to put in the tooltip, making that number determine a color seems like it would be simple, almost as simple as appending it to the tooltip. (if indeed that's all that's missing.)
