UPDATE!
We have just released Preview 3 for 4.21! Thank you for your continued help in testing the 4.21 build before its official release. As a reminder, the Preview builds are for testing only, and should not be used for the active development of your project.
For a list of known issues affecting this latest preview, please follow the links provided on the first post in this thread.
Fixed in Preview 3
Fixed! UE-64745 Audio: Spatialization: Plugins: Stereo files using Resonance will play in silence
Fixed! UE-63295 Audio Attenuation falloff is applied even when turned off when called in Blueprints
Fixed! UE-63471 Crash on Level Reload in Standalone when Set Sound Mix Class Override is called
Fixed! UE-64896 Pitching/Buffer tears when VOIP is set to anything besides 48kHz
Fixed! UE-65477 Fix up template code generation for source effects
Fixed! UE-65472 Removing Master Submix Effect in BP causes Crash
Fixed! UE-65339 2017 Epic Copyright in source and plugin code
Fixed! UE-65127 Hot Reload fails when project code class that derives from a plugin code class is modified
Fixed! UE-65262 Core install fails to build with ERROR: Source file ‘APEX_ClothingPROFILE_x64.pdb’ does not exist
Fixed! UE-65253 Can’t safely include ATL headers\libs in 4.20
Fixed! UE-65392 Visual Studio always prompts to save solution
Fixed! UE-65189 Unable to package plugins in 4.21
Fixed! UE-65316 Cannonballs fire offset from cannons in StrategyGame
Fixed! UE-65153 UndoBufferSize too small to store mesh processing operations
Fixed! UE-65167 Import of DWG crash Unreal if file already open with another application
Fixed! UE-65228 Generate and mount DDC pack file for Enterprise templates
Fixed! UE-63741 Warning occurs when opening project - Warning: BoolProperty FLiveLinkInterpolationSettings::bUseInterpolation is not initialized properly
Fixed! UE-65182 Editor Crashes When Attempting to Create/Open a Blueprint While ‘Show Friendly Variable Names’ is False
Fixed! UE-64601 Composite Curve Tables do not properly update when undoing actions
Fixed! UE-64631 Random crash adding array elements to Gameplay Tag editor
Fixed! UE-64585 Adding/Removing a member variable to/from a struct removes the Parent Table from the Composite Data Table
Fixed! UE-62857 Composite Data/Curve Table Properties not updated when parent table is reimported
Fixed! UE-63602 You can set restricted tags that already have non-restricted children to not allow non-restricted children
Fixed! UE-62585 Ensure when interacting with a blueprint in the level that has multiple audio components
Fixed! UE-62498 [CrashReport] UE4Editor_Kismet!SSCSEditor::AddTreeNode() [sscseditor.cpp:5781]
Fixed! UE-65482 Crash when aborting rename of a component when a component when the same name has been added to its archetype
Fixed! UE-62686 One-off crash setting name of duplicate in-world component to blank
Fixed! UE-65407 Linux: crash when running QAGameEditor in -game mode
Fixed! UE-63459 Linux to Linux Launch-On fails with Errors - VulkanRHI:vkDeviceWaitIdle(Device) failed, VkResult=-4
Fixed! UE-63092 Crash Alt-Tabbing out of -game on Linux with -
Fixed! UE-64142 Volumetric Fog causing Black Artifacting on Particle and Rect Lights
Fixed! UE-64138 Movable Volumetric Fog causing Flickering Lighting when Navigating in the Viewport
Fixed! UE-65290 SceneCapture2D Crashes When Changing to a Mobile Preview
Fixed! UE-65273 Remote Building for iOS Fails During Build Step: “GetBuildPlatform: No BuildPlatform found for IOS”
Fixed! UE-65268 Software Occlusion Culling setting is missing in UI
Fixed! UE-65131 TM-Decals Crashes on Open on tvOS with Metal Desktop-Forward Renderer Enabled
Fixed! UE-65178 bDisableExposure Exposure bias on Mobile
Fixed! UE-65143 GitHub 5166 : Exposure bias does not work on mobile anymore.
Fixed! UE-64891 tvOS crash on launch "Failed to generate a render pipeline state object: Target OS incompatible "
Fixed! UE-64591 New Mobile PIE doesn’t remember size setting from previous session
Fixed! UE-64588 Make new mobile PIE always aware of high-DPI when in 1x mode
Fixed! UE-63286 Some HUD elements don’t scale with new mobile PIE
Fixed! UE-63269 New Mobile PIE drop-down covers bezel
Fixed! UE-63102 Metallic Materials Get Darker When Directional Light Is Set to Movable
Fixed! UE-64518 New Mobile PIE is a very small size on 4K monitor
Fixed! UE-64464 HTML5 WebGL1 crash in GLSL1 shader compiler
Fixed! UE-64383 MSAA depthbuffer never be released on Android
Fixed! UE-65439 Editor viewport does not grab mouse control during PIE
Fixed! UE-65321 Android crash: java.lang.NoSuchMethodError: android.view.Display.getPresentationDeadlineNanos
Fixed! UE-65324 Mac: Editor Crashes When Applying Several Material Changes at Once
Fixed! UE-65384 GitHub 5178 : Fixed issue that array size for termination character is not enough.
Fixed! UE-65374 Windows has a couple UnknownRHI’s
Fixed! UE-65218 GitHub 5173 : Fix for GetAndOrCreateGraphicsPipelineState errors reported every 10 seconds
Fixed! UE-64952 Dx12 Content Examples Crash when exiting the editor
Fixed! UE-65455 Remove DirectX 11 Mobile Emulation RHIs
Fixed! UE-65454 Packaged projects do not open with DirectX11 Mobile Emulation
Fixed! UE-64580 Web Browser UMG Widget Does Not Work in DX12
Fixed! UE-61675 DX12 KiteDemo editor crashes on launch, Device->CreatePipelineState(Desc, IID_PPV_ARGS(&PSO)) failed
Fixed! UE-63134 Particle Effects Stop Animating in PIE in -
Fixed! UE-63749 TangentCalc_Anim does not animate in PIE on Linux with
Fixed! UE-64419 Crash closing packaged InfiltratorDemo while running with -dx12
Fixed! UE-65474 Packaged Builds with DX12 Crash on 2nd Start
Fixed! UE-65457 Crash launching project with Compat.MAX_GPUSKIN_BONES=75 and Preview Rendering set to Shader Model 5
Fixed! UE-64989 ShooterGame UI is missing components on Mac
Fixed! UE-65053 HUD not appearing for VehicleAdvGameMode on Mac
Fixed! UE-63107 AMD Linux encounters handled ensure: CmdBuffer -> IsOutsideRenderPass, and then the editor closes
Fixed! UE-63754 Recompute Tangents causes MorphDown example to render incorrect on Linux
Fixed! UE-65166 Ensures when sculpting landscape in -, UpdateRegion.SrcY == 0 in VulkanTexture.cpp
Fixed! UE-44076 Crash When Opening Static Mesh After Enabling Forward Shading And Disabling “Support Stationary Skylight”
Fixed! UE-65301 Default asset names for new Material Layers and Material Layer Blends should not contain “MaterialFunction”
Fixed! UE-64838 Reset Layout option does not reset layout to default in Subeditor Windows
Fixed! UE-64961 Slow Task windows pop up even when they are set to invisible
Fixed! UE-64273 Ensure jumping to a cleared bookmark
Fixed! UE-62477 Cascade Beam Emitter Lifetime Module Is Broken
Fixed! UE-65305 Editor crashed using MRU Content Browser filter
Fixed! UE-65293 New Material Layers and Material Layer Blends have compilation errors for their material attribute input and output counts on open
Fixed! UE-65238 Missing icon on Media Player timeline scrubber when hovered on
Fixed! UE-64874 Cannot add an emitter asset to a system by double clicking in the New System Wizard
Fixed! UE-64869 Double Click templates in the New Emitter Wizard does not create the Emitter/System
Fixed! UE-65001 Crash when using Skeletal Mesh DataInterface’s RandomVertex in conjunction with Sampling Regions
Fixed! UE-64705 Emitters added to the New System Wizard cannot be removed
Fixed! UE-65475 Huge CPU stall when using GPU particles.
Fixed! UE-65420 Crash when sampling a pseudo volume texture CPU
Fixed! UE-65418 Crash when saving an emitter in a debug build.
Fixed! UE-59926 New Parameters added to the Stack from the Parameters Panel are not initialized
Fixed! UE-65227 Crash when setting an emitter to GPU and hitting spacebar rapidly to restart it
Fixed! UE-64987 Crash on compiling Emitter with Sample Skeletal Mesh Surface module where assigned Default Mesh already has CPU access
Fixed! UE-65078 Anim Class dropdown menus for skeletal mesh assets glitch
Fixed! UE-64214 Clicking on object causes EndInputTouch to fire on the press instead of the release
Fixed! UE-65281 Unable to move items added to the Canvas of a Widget Blueprint with Mouse Click and Drag
Fixed! UE-65337 Windows Mixed Reality - WMR fixes are missing from release 4.21
Fixed! UE-65373 Autosave packages is including map built data
REMEMBER: Please report any new bugs you find by following the How To Report a Bug Guide