Missing Script references in the SolverExamples scene.
48a9ac506c430325340e248c8421604e54de1804

@radicalad Any idea what these might have been?

Looks like it was a Solver Controller Finder script, which no longer exists in favor of Solver Handler inheriting ControllerFinder.
So just removing the script references is a valid fix?
Yep. I tested it when we switched to ControllerFinder -> SolverHandler. I just didn't notice the missing script references because everything ran fine. Sorry guys - my bad.