An OmniBrowser Debugger?

The Squeak debugger (1396 lines of code) is hard to understand and impossible to extend. The OmniBrowser framework is powerful and enables one to build extensible meta-driven browsers. Yesterday evening I thought that it would be the time to bring the two things together:

The screenshot shows an initial prototype of an OmniBrowser based debugger (237 lines of code). It provides all the functionality of the original debugger, with the exception of the inspector panes that I personally don't find that useful anyway (this is an excuse for not having implemented them).

Did I already mention that this debugger can be easily extended with new functionality? What about capturing a continuation at every step to have a back button like in the web browser? The possibilities are endless ...