> No, OBNotifier was my attempt at a simple way to handle updating the 
> browser when the system is changed by something other than that browser. 
> It had nothing to do with OBNotification.

I said it was a guess  :-)

>> The best solution I found was to explore "Smalltalk obsoleteClasses".  
>> It turns out that anObsoleteNotifier was at: 29, so I did "(Smalltalk obsoleteClasses 
>> at: 29) becomeForward: OBNotification class", which seems to have done the trick.

> I'm surprised this hasn't caused you any problems. If you find yourself 
> in this situation again, the best way to fix it is to send #unregister 
> to the instance of OBNotifier. For this image, I think you want 
> something like the following. I don't have a Squeak image handy, so I 
> can't check this code...

> SystemChangeNotifier uniqueInstance noMoreNotificationsFor: 
> theObsoleteOBNotifer.

(Smalltalk obsoleteClasses at: 29) allInstances do: [:i | SystemChangeNotifier uniqueInstance noMoreNotificationsFor: i].

did the job.

I don't think you can access obsolete classes by name.

>> Is this a general technique to use after renaming classes?

> In general, you shouldn't need to do this kind of thing. Renaming a 
> class should "just work." (Although this was a case of removing a 
> class.) This was a pretty ugly hack that I didn't clean up properly when 
> I took it out. I'll add the clean up code to the OB installer.

Thanks for the heads up,

Colin