WPF Quirks: "This freezable can not be frozen" when changing Windows system theme

The scenario is easy enough to create: make a Brush, use a Binding as the Color property, use your brush in your app, then start the application and change the system theme. An error "This freezable can not be frozen" will be triggered. The solution is to set x:Shared="False" for the brushes with color bindings.

An entire Microsoft Connect page is devoted to this issue, so get all the details there: Changing system theme throws "This freezable can not be frozen" exception

Update February 2016: The Microsoft Connect page has disappeared. Maybe it was because the bug was marked as "closed - by design", or some other Microsoft site revamp idiocy.