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Reproduction is extremely easy.
1. Add to any page PasswordBox
2. Run app
3. See "A first chance exception of type 'System.IO.FileNotFoundException' occurred in mscorlib.ni.dll" in output.
4. Also, if to set break at exceptions (Ctrl+Alt+E), mark checkbox "CLR exeptions", then debugger would show window with recommendations, but no useful details there.
I didn't check release mode, but in debug mode, this makes a notable slowdown (several seconds) during the page loading.
I'd set this problem to High priority.
1. Add to any page PasswordBox
2. Run app
3. See "A first chance exception of type 'System.IO.FileNotFoundException' occurred in mscorlib.ni.dll" in output.
4. Also, if to set break at exceptions (Ctrl+Alt+E), mark checkbox "CLR exeptions", then debugger would show window with recommendations, but no useful details there.
I didn't check release mode, but in debug mode, this makes a notable slowdown (several seconds) during the page loading.
I'd set this problem to High priority.