I have a view that got a different id [*]. Existing users will get an error when starting with an existing workspace where the view was open. I wonder if there is a way to automatically use the new view instead (or to detect the error and handle it that way).
[*] It's a legacy navigator view that used ComonNavigator and added a bunch of stuff just to make it on par with the ProjectExplorer. I thought I'd just as well use the latter directly, but all the 3rd party extensions are referring the original viewer id, so I can't reuse mine.
I solved it by looking for it in the plugin activator and asking the user if we can reset the perspective. It would have been nicer if there was a way to open automatically the PE view in the same stack as the CN, so that a reset would not have been necessary. I guess the pre-e4 APIs don't expose that kind of details.