>Using HTML will be harder than using RTF. The container has to have the events for enabling the colorizing/underlining of the item when a mouse is moved over it. The ActiveX container for RTF already has this event that can be used; you will have to find a similar event for the HTML. Possibly using an embedded browser display might have these events.

That's not much of a problem, just a few lines of embedded stylesheet (with a hover modifier for the class), and the browser object would handle that. The trouble with that approach is that the browser object is the IE and it defaults to version 7 which is way behind from whatever the current fashion in css is, and IOW doesn't support many features and does others quite wrong. Just tracking which features are supported and which display wrongly and which ugly is a full day job.

Anatoliy found a registry thing somewhere - in HKCU\Software\Microsoft\Internet Explorer\Main\FeatureControl\FEATURE_BROWSER_EMULATION you need to insert a value with name of your exe (no path) as the key and a dword value of IE version you want (in milliseconds, i.e. for IE 11 you need to put 11000). Then it works for the next launch of your app, so if you do that from within the app, it will look fugly the first time. I really wish there was a different browser object we could use as a COM object with at least that much access as with IE.

OTOH, RTF has its own quirks, the specs were changed a couple of times (since 22 years ago when I first tried to code for it) and is still rather easy to do if you stay with just simple stuff. At least it's abandonware, so no new bugs.