February 11, 2020-KB4534119 Cumulative Update for .NET Framework 3.5 and 4.7.2 for Windows 10 Version 1809 and Windows Server 2019

WPF¹

- Addresses a hang and eventual StackOverflowException arising when opening a RibbonSplitButton, if the app programmatically disables the button and replaces its menu items before the user releases the mouse button.

- Addresses a reliability problem that reduces crashes when running in Software Rendering mode.

- Addresses a hang arising during layout of Grids with columns belonging to a SharedSizeGroup.

- Addresses certain hangs that can arise while scrolling a TreeView.

Winforms

- Addresses an issue in System.Windows.Forms.TextBox controls with ImeMode property set to NoControl. These controls now retain IME setting consistent with the OS setting regardles of the order of navigation on the page. Fix applies to CHS with pinyin keyboard.

- Addresses an issue with System.Windows.Forms.ComboBox control with ImeMode set to ImeMode.NoControl on CHS with Pinyin keyboard to retain input mode of the parent container control instead of switching to disabled IME when navigating using mouse clicks and when focus moves from a control with disabled IME to this ComboBox control.

WCF²

- Added opt-in retry mechanism when configuring listening endpoints on the WCF Activation service to address potential race condition when rapidly restarting an IIS application multiple times while under high CPU load which resulted in an endpoint being inaccessible. Customers can opt in to the fix by adding the following AppSetting to SMSvcHost.exe.config under the %windir%\Microsoft.NET\Framework\v4.0.30319 and %windir%\Microsoft.NET\Framework64\v4.0.30319 folders as appropriate. This will retry registering an endpoint 10 times with a 1 second delay between each attempt before placing the endpoint in a failure state.

<appSettings>
<add key="wcf:SMSvcHost:listenerRegistrationRetryCount" value="10"/>
<add key="wcf:SMSvcHost:listenerRegistrationRetryDelayms" value="1000"/>
</appSettings>

CLR³

- There is a race condition in the portable PDB metadata provider cache that leaked providers and caused crashes in the diagnostic StackTrace API. To fix the race, detect the cause where the provider wasn't being disposed and dispose it.

SQL

- Addresses an issue with SqlClient Bid traces where information wasn’t being printed due to incorrectly formatted strings.