WPF .Net Core 3.1 applications not DPI Aware in VS2019 v16.11.3

[vsfeedback]

This issue has been moved from a ticket on Developer Community.

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[severity:It's more difficult to complete my work] [regression] [worked-in:VS2019 ver16.11.2]
WPF .Net Core 3.1 applications were DPI aware before the latest update to VS2019 v16.11.3.

A workaround is adding an application manifest file to the solution and setting DPI awareness, but this shouldn't be necessary. To reproduce this bug please follow my steps below in Test 1.

The other tests show DPI awareness working for WPF .Net Core 3.1 in VS2019 v16.11.2 (Test 2) and WPF .Net 5 in VS2019 v16.11.3 (Test3).

My test is on a High DPI Display: I'm using 4K monitor, 3840 x 2160, display set at 250%

Test 1 (FAIL): WPF Core3.1 application in VS2019 v16.11.3

1. Launch VS2019 v16.11.3
2. Create new WPF project and target framework .Net Core 3.1
3. Drag a button from Toolbox and drop onto MainWindow design surface
4. Run application.
5. FAIL. Window and Button are not DPI aware.
   WPFNetCore3.1_VS2019ver16.11.3_FAIL. PNG

Test 2 (SUCCESS): WPF Core3.1 application in VS2019 ver16.11.2 (NOTE: this is the previous version of VS2019)

1. Launch VS2019 v16.11.2
2. Create new WPF project and target framework .Net Core 3.1
3. Drag a button from Toolbox and drop onto MainWindow design surface
4. Run application.
5. SUCCESS. Window and Button are DPI aware.
   WPFCore3.1_VS2019ver16.11.2_SUCCESS. PNG

Test 3 (SUCCESS): WPF .Net 5 application in VS2019 ver16.11.3

1. Launch VS2019 v16.11.3
2. Create new WPF project and target framework .Net 5
3. Drag a button from Toolbox and drop onto MainWindow design surface
4. Run application.
5. SUCCESS. Window and Button are DPI aware.
   WPFNet5_VS2019ver16.11.3_SUCCESS. PNG

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Original Comments

Feedback Bot on 9/27/2021, 11:57 PM:

We have directed your feedback to the appropriate engineering team for further evaluation. The team will review the feedback and notify you about the next steps.

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Original Solutions

(no solutions)

[ryalanms]

This is a duplicate of #5377. The fix is in 3.1.21.