Fix (workaround, actually) for bug #844676: deselecting "show hidden" can
cause an index error. We now select the first package if this threatens
to happen. Will backport.
diff --git a/Mac/Tools/IDE/PackageManager.py b/Mac/Tools/IDE/PackageManager.py
index fb482ef..4bd0e62 100755
--- a/Mac/Tools/IDE/PackageManager.py
+++ b/Mac/Tools/IDE/PackageManager.py
@@ -383,6 +383,8 @@
 			self.w.user_button.enable(0)
 		else:
 			sel = sel[0]
+			if sel >= len(self.packages):
+				sel = 0
 			self.w.packagebrowser.setselection([sel])
 			installed, message = self.getstatus(sel)
 			self.w.installed.set(installed)