Bug explanation

Views containing a TabControl using any style based on MaterialDesignTabControlBase are never garbage collected due to a problem in ScrollViewerAssist when the attached property SupportHorizontalScroll is enabled.

ScrollViewerAssist registers a HwndSourceHook to handle Win32 messages but never unregisters it.

This shows the memory snapshot from my application (class names obfuscated for reasons of paranoia and over-zealous corporate IT security).

PR to follow!

Version

4.8.0