Known Issues in changelog

README.md

 
 - ####  2021.2 Release 2 : (12.1.1 rev1 2021-12-10)
   - **Updated HD Render Pipeline / Visual Effect Graph to 12.1.1**
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+  - **Known Issues **
+      - Prewarm delta time consideration (fixed in 2021.2.10f1)
+      - Mac M1 build: scene flickering issue 
+      - Linux build: "Vulkan - out of memory" issue
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 - ####  2021.2 Release 1 : (12.1.1 rev1 2021-11-29)
 
   - **Updated HD Render Pipeline / Visual Effect Graph to 12.1.1**