Issue since upgrading to KDE 4.1.3: Opera browser crashing

When I had KDE 4.0.4, Opera might crash about once every few weeks. on average. Since I switched over to KDE 4.1.3, it’s crashed about 8 times in 2 days. I’m visiting the same sites. So my questions are:

  1. How do I diagnose this issue?
  2. Is there a way to find out what errors occur when an app crashes?
  3. Has anyone else noticed this?
  4. When installing a new desktop, is something like this common? Does reinstalling the app usually solve such issues?