10 second lag between opening any image

[NinthDesertDude]

On version 4.3.11, and not on version 4.3.10, I have a long delay on the scale of about 10 seconds between opening any image. Doubtful I'm the only one to experience it, so I figured I'd open a bug for it. This doesn't repro on v4.3.10. This delay will happen image-by-image if I try to load multiple at once, so it quickly becomes an unacceptably long delay. No change to hardware, no manual changes to drivers, repros consistently. It happens even with no 3rd-party plugins installed / on a fresh install. There is no delay for pasted images or the default blank image when opening paint.net, only for images opened by the file browser or drag-n-drop. The delay exists both with hardware accelerated rendering on, or off.

Here's a copy of the diagnostics from version 4.3.11 if that helps.
 

Spoiler

Application                                                  paint.net 4.3.11 (Stable 4.311.8179.42221)
Build Date                                                   Tuesday, May 24, 2022
Install type                                                 Portable

Hardware accelerated rendering (GPU)                         True
Remote session                                               False
Animations                                                   False
DPI                                                          96 (1.00x scale)
Language                                                     en-US

OS                                                           Windows 10 Home x64 (10.0.19044.0)
Runtime                                                      .NET 6.0.5 x64
Physical Memory                                              7,934 MB

CPU                                                          Intel(R) Core(TM) i5-1035G1 CPU @ 1.00GHz
    Speed                                                    ~1190 MHz
    Cores / Threads                                          4 / 8
    Features                                                 SSE, SSE2, SSE3, SSSE3, SSE4_1, SSE4_2, AVX, AVX2

Pointer                                                      Virtual Multitouch Device
    Type                                                     ExternalPen
    Contacts                                                 1

Video Card                                                   Intel(R) UHD Graphics
    Dedicated Video RAM                                      128 MB
    Dedicated System RAM                                     0 MB
    Shared System RAM                                        3,967 MB
    Vendor ID                                                0x8086
    Device ID                                                0x8A56
    Subsystem ID                                             0x3FB517AA
    Revision                                                 7
    LUID                                                     0x00012AA9
    Flags                                                    AcgCompatible, SupportMonitoredFences, KeyedMutexConformance
    Graphics Preemption                                      TriangleBoundary
    Compute Preemption                                       ThreadBoundary
    Outputs                                                  1
    Feature Level                                            Direct3D_12_1
    DXGI Formats                                             A8_UNorm, B8G8R8A8_UNorm, R16G16B16A16_UNorm, R16G16B16A16_Float, R32G32B32A32_Float
    Buffer Precision                                         UNorm8bpc, UNorm8bpcSrgb, UNorm16bpc, Float16bpc, Float32bpc
    Maximum Bitmap Size                                      16384

Video Card                                                   Microsoft Basic Render Driver
    Dedicated Video RAM                                      0 MB
    Dedicated System RAM                                     0 MB
    Shared System RAM                                        3,967 MB
    Vendor ID                                                0x1414
    Device ID                                                0x008C
    Subsystem ID                                             0x00000000
    Revision                                                 0
    LUID                                                     0x00012D04
    Flags                                                    Software, AcgCompatible, SupportMonitoredFences, KeyedMutexConformance
    Graphics Preemption                                      InstructionBoundary
    Compute Preemption                                       InstructionBoundary
    Outputs                                                  0
    Feature Level                                            Direct3D_12_1
    DXGI Formats                                             A8_UNorm, B8G8R8A8_UNorm, R16G16B16A16_UNorm, R16G16B16A16_Float, R32G32B32A32_Float
    Buffer Precision                                         UNorm8bpc, UNorm8bpcSrgb, UNorm16bpc, Float16bpc, Float32bpc
    Maximum Bitmap Size                                      8388608

Managed assemblies                                           88
    System.Private.CoreLib                                   .\System.Private.CoreLib.dll, Version=6.0.0.0, PublicKeyToken=7cec85d7bea7798e
    paintdotnet                                              .\paintdotnet.dll, Version=4.311.8179.42221
    System.Runtime                                           .\System.Runtime.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    System.Windows.Forms                                     .\System.Windows.Forms.dll, Version=6.0.2.0, PublicKeyToken=b77a5c561934e089
    PaintDotNet.Base                                         .\PaintDotNet.Base.dll, Version=4.311.8179.42221
    System.Collections.Concurrent                            .\System.Collections.Concurrent.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    System.Diagnostics.Process                               .\System.Diagnostics.Process.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    PaintDotNet.SystemLayer                                  .\PaintDotNet.SystemLayer.dll, Version=4.311.8179.42221
    TerraFX.Interop.Windows                                  .\TerraFX.Interop.Windows.dll, Version=10.0.20348.0, PublicKeyToken=35b01b53313a6f7e
    System.Runtime.InteropServices.RuntimeInformation        .\System.Runtime.InteropServices.RuntimeInformation.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    System.Runtime.InteropServices                           .\System.Runtime.InteropServices.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    PaintDotNet.SystemLayer.Native.x64                       .\PaintDotNet.SystemLayer.Native.x64.dll, Version=4.311.8179.42221
    System.Threading                                         .\System.Threading.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    System.Runtime.Extensions                                .\System.Runtime.Extensions.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    System.Runtime.CompilerServices.VisualC                  .\System.Runtime.CompilerServices.VisualC.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    System.Collections.NonGeneric                            .\System.Collections.NonGeneric.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    System.Runtime.Intrinsics                                .\System.Runtime.Intrinsics.dll, Version=6.0.0.0, PublicKeyToken=cc7b13ffcd2ddd51
    PaintDotNet.Core                                         .\PaintDotNet.Core.dll, Version=4.311.8179.42221
    System.Private.Uri                                       .\System.Private.Uri.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    System.ComponentModel.Primitives                         .\System.ComponentModel.Primitives.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    System.Windows.Forms.Primitives                          .\System.Windows.Forms.Primitives.dll, Version=6.0.2.0, PublicKeyToken=b77a5c561934e089
    WindowsBase                                              .\WindowsBase.dll, Version=6.0.2.0, PublicKeyToken=31bf3856ad364e35
    System.Drawing.Primitives                                .\System.Drawing.Primitives.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    PresentationFramework                                    .\PresentationFramework.dll, Version=6.0.2.0, PublicKeyToken=31bf3856ad364e35
    System.Xaml                                              .\System.Xaml.dll, Version=6.0.2.0, PublicKeyToken=b77a5c561934e089
    System.ComponentModel                                    .\System.ComponentModel.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    System.Diagnostics.TraceSource                           .\System.Diagnostics.TraceSource.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    System.Collections                                       .\System.Collections.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    System.Threading.Thread                                  .\System.Threading.Thread.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    System.Text.Encoding.CodePages                           .\System.Text.Encoding.CodePages.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    PaintDotNet.Resources                                    .\PaintDotNet.Resources.dll, Version=4.311.8179.42221
    Newtonsoft.Json                                          .\Newtonsoft.Json.dll, Version=13.0.0.0, PublicKeyToken=30ad4fe6b2a6aeed
    Microsoft.Win32.Primitives                               .\Microsoft.Win32.Primitives.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    System.Linq.Expressions                                  .\System.Linq.Expressions.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    System.ComponentModel.TypeConverter                      .\System.ComponentModel.TypeConverter.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    System.ObjectModel                                       .\System.ObjectModel.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    System.Runtime.Numerics                                  .\System.Runtime.Numerics.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    PaintDotNet.Data                                         .\PaintDotNet.Data.dll, Version=4.311.8179.42221
    System.Configuration.ConfigurationManager                .\System.Configuration.ConfigurationManager.dll, Version=6.0.0.0, PublicKeyToken=cc7b13ffcd2ddd51
    System.Collections.Specialized                           .\System.Collections.Specialized.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    System.Xml.ReaderWriter                                  .\System.Xml.ReaderWriter.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    System.Private.Xml                                       .\System.Private.Xml.dll, Version=6.0.0.0, PublicKeyToken=cc7b13ffcd2ddd51
    PaintDotNet.Framework                                    .\PaintDotNet.Framework.dll, Version=4.311.8179.42221
    System.Net.WebClient                                     .\System.Net.WebClient.dll, Version=6.0.0.0, PublicKeyToken=cc7b13ffcd2ddd51
    System.ComponentModel.EventBasedAsync                    .\System.ComponentModel.EventBasedAsync.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    System.Memory                                            .\System.Memory.dll, Version=6.0.0.0, PublicKeyToken=cc7b13ffcd2ddd51
    System.Text.Encoding.Extensions                          .\System.Text.Encoding.Extensions.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    System.Collections.Immutable                             .\System.Collections.Immutable.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    Microsoft.Win32.SystemEvents                             .\Microsoft.Win32.SystemEvents.dll, Version=6.0.0.0, PublicKeyToken=cc7b13ffcd2ddd51
    System.Threading.ThreadPool                              .\System.Threading.ThreadPool.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    System.Drawing.Common                                    .\System.Drawing.Common.dll, Version=6.0.0.0, PublicKeyToken=cc7b13ffcd2ddd51
    Microsoft.Win32.Registry                                 .\Microsoft.Win32.Registry.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    System.Linq                                              .\System.Linq.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    PresentationCore                                         .\PresentationCore.dll, Version=6.0.2.0, PublicKeyToken=31bf3856ad364e35
    DirectWriteForwarder                                     .\DirectWriteForwarder.dll, Version=6.0.2.0, PublicKeyToken=31bf3856ad364e35
    System.Diagnostics.Debug                                 .\System.Diagnostics.Debug.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    UIAutomationTypes                                        .\UIAutomationTypes.dll, Version=6.0.2.0, PublicKeyToken=31bf3856ad364e35
    Accessibility                                            .\Accessibility.dll, Version=4.0.0.0, PublicKeyToken=31bf3856ad364e35
    System.Numerics.Vectors                                  .\System.Numerics.Vectors.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    System.IO.Packaging                                      .\System.IO.Packaging.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    System.Diagnostics.FileVersionInfo                       .\System.Diagnostics.FileVersionInfo.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    PaintDotNet.Effects                                      .\PaintDotNet.Effects.dll, Version=4.311.8179.42221
    System.Threading.Tasks.Parallel                          .\System.Threading.Tasks.Parallel.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    System.Runtime.CompilerServices.Unsafe                   .\System.Runtime.CompilerServices.Unsafe.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    System.Runtime.Loader                                    .\System.Runtime.Loader.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    WebPFileType                                             .\Bundled\WebPFileType\WebPFileType.dll, Version=1.3.12.0
    AvifFileType                                             .\Bundled\AvifFileType\AvifFileType.dll, Version=1.1.19.0
    DdsFileTypePlus                                          .\Bundled\DDSFileTypePlus\DdsFileTypePlus.dll, Version=1.10.12.0
    System.Diagnostics.Tracing                               .\System.Diagnostics.Tracing.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    System.Reflection.MetadataLoadContext                    .\System.Reflection.MetadataLoadContext.dll, Version=6.0.0.0, PublicKeyToken=cc7b13ffcd2ddd51
    System.Reflection.Metadata                               .\System.Reflection.Metadata.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    System.IO.MemoryMappedFiles                              .\System.IO.MemoryMappedFiles.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    DynamicDraw                                              .\Effects\DynamicDraw\DynamicDraw.dll, Version=3.3.0.38292
    System.Resources.Extensions                              .\System.Resources.Extensions.dll, Version=6.0.0.0, PublicKeyToken=cc7b13ffcd2ddd51
    System.Drawing                                           .\System.Drawing.dll, Version=6.0.2.0, PublicKeyToken=b03f5f7f11d50a3a
    System.Runtime.Serialization.Formatters                  .\System.Runtime.Serialization.Formatters.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    mscorlib                                                 .\mscorlib.dll, Version=4.0.0.0, PublicKeyToken=b77a5c561934e089
    System.Security.Claims                                   .\System.Security.Claims.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    System.CodeDom                                           .\System.CodeDom.dll, Version=6.0.0.0, PublicKeyToken=cc7b13ffcd2ddd51
    System.Text.RegularExpressions                           .\System.Text.RegularExpressions.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    System.Private.Xml.Linq                                  .\System.Private.Xml.Linq.dll, Version=6.0.0.0, PublicKeyToken=cc7b13ffcd2ddd51
    System.Xml.XDocument                                     .\System.Xml.XDocument.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    System.IO.Compression                                    .\System.IO.Compression.dll, Version=6.0.0.0, PublicKeyToken=b77a5c561934e089
    System.Runtime.Serialization.Primitives                  .\System.Runtime.Serialization.Primitives.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    System.Console                                           .\System.Console.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    System.Diagnostics.StackTrace                            .\System.Diagnostics.StackTrace.dll, Version=6.0.0.0, PublicKeyToken=b03f5f7f11d50a3a
    PresentationFramework-SystemXmlLinq                      .\PresentationFramework-SystemXmlLinq.dll, Version=6.0.2.0, PublicKeyToken=b77a5c561934e089
    System.Xml.Linq                                          .\System.Xml.Linq.dll, Version=4.0.0.0, PublicKeyToken=b77a5c561934e089

Native modules                                               182
    paintdotnet.exe                                          .\paintdotnet.exe, version=4.311.8179.42221
    ntdll.dll                                                C:\Windows\SYSTEM32\ntdll.dll, version=10.0.19041.1566 (WinBuild.160101.0800)
    KERNEL32.DLL                                             C:\Windows\System32\KERNEL32.DLL, version=10.0.19041.1566 (WinBuild.160101.0800)
    KERNELBASE.dll                                           C:\Windows\System32\KERNELBASE.dll, version=10.0.19041.1566 (WinBuild.160101.0800)
    USER32.dll                                               C:\Windows\System32\USER32.dll, version=10.0.19041.1 (WinBuild.160101.0800)
    win32u.dll                                               C:\Windows\System32\win32u.dll, version=10.0.19041.1645 (WinBuild.160101.0800)
    GDI32.dll                                                C:\Windows\System32\GDI32.dll, version=10.0.19041.1620 (WinBuild.160101.0800)
    gdi32full.dll                                            C:\Windows\System32\gdi32full.dll, version=10.0.19041.1620 (WinBuild.160101.0800)
    msvcp_win.dll                                            C:\Windows\System32\msvcp_win.dll, version=10.0.19041.789 (WinBuild.160101.0800)
    ucrtbase.dll                                             C:\Windows\System32\ucrtbase.dll, version=10.0.19041.789 (WinBuild.160101.0800)
    SHELL32.dll                                              C:\Windows\System32\SHELL32.dll, version=10.0.19041.964 (WinBuild.160101.0800)
    ADVAPI32.dll                                             C:\Windows\System32\ADVAPI32.dll, version=10.0.19041.1 (WinBuild.160101.0800)
    msvcrt.dll                                               C:\Windows\System32\msvcrt.dll, version=7.0.19041.546 (WinBuild.160101.0800)
    sechost.dll                                              C:\Windows\System32\sechost.dll, version=10.0.19041.1 (WinBuild.160101.0800)
    RPCRT4.dll                                               C:\Windows\System32\RPCRT4.dll, version=10.0.19041.1 (WinBuild.160101.0800)
    IMM32.DLL                                                C:\Windows\System32\IMM32.DLL, version=10.0.19041.546 (WinBuild.160101.0800)
    hostfxr.dll                                              .\hostfxr.dll, version=6,0,522,21309 @Commit: 70ae3df4a6f3c92fb6b315afc405edd10ff38579
    hostpolicy.dll                                           .\hostpolicy.dll, version=6,0,522,21309 @Commit: 70ae3df4a6f3c92fb6b315afc405edd10ff38579
    coreclr.dll                                              .\coreclr.dll, version=6,0,522,21309 @Commit: 70ae3df4a6f3c92fb6b315afc405edd10ff38579
    ole32.dll                                                C:\Windows\System32\ole32.dll, version=10.0.19041.1320 (WinBuild.160101.0800)
    combase.dll                                              C:\Windows\System32\combase.dll, version=10.0.19041.1320 (WinBuild.160101.0800)
    OLEAUT32.dll                                             C:\Windows\System32\OLEAUT32.dll, version=10.0.19041.985 (WinBuild.160101.0800)
    bcryptPrimitives.dll                                     C:\Windows\System32\bcryptPrimitives.dll, version=10.0.19041.1415 (WinBuild.160101.0800)
    System.Private.CoreLib.dll                               .\System.Private.CoreLib.dll, version=6.0.522.21309
    clrjit.dll                                               .\clrjit.dll, version=6,0,522,21309 @Commit: 70ae3df4a6f3c92fb6b315afc405edd10ff38579
    kernel.appcore.dll                                       C:\Windows\SYSTEM32\kernel.appcore.dll, version=10.0.19041.546 (WinBuild.160101.0800)
    paintdotnet.dll                                          .\paintdotnet.dll, version=4.311.8179.42221
    System.Runtime.dll                                       .\System.Runtime.dll, version=6.0.522.21309
    uxtheme.dll                                              C:\Windows\system32\uxtheme.dll, version=10.0.19041.1 (WinBuild.160101.0800)
    System.Windows.Forms.dll                                 .\System.Windows.Forms.dll, version=6.0.422.16407
    PaintDotNet.Base.dll                                     .\PaintDotNet.Base.dll, version=4.311.8179.42221
    icu.dll                                                  C:\Windows\SYSTEM32\icu.dll, version=64, 2, 0, 0 (WinBuild.160101.0800)
    System.Collections.Concurrent.dll                        .\System.Collections.Concurrent.dll, version=6.0.522.21309
    System.Diagnostics.Process.dll                           .\System.Diagnostics.Process.dll, version=6.0.522.21309
    PaintDotNet.SystemLayer.dll                              .\PaintDotNet.SystemLayer.dll, version=4.311.8179.42221
    TerraFX.Interop.Windows.dll                              .\TerraFX.Interop.Windows.dll, version=10.0.20348.0
    System.Runtime.InteropServices.RuntimeInformation.dll    .\System.Runtime.InteropServices.RuntimeInformation.dll, version=6.0.522.21309
    System.Runtime.InteropServices.dll                       .\System.Runtime.InteropServices.dll, version=6.0.522.21309
    vcruntime140.dll                                         .\vcruntime140.dll, version=14.32.31326.0
    vcruntime140_1.dll                                       .\vcruntime140_1.dll, version=14.32.31326.0
    msvcp140.dll                                             .\msvcp140.dll, version=14.32.31326.0
    msvcp140_1.dll                                           .\msvcp140_1.dll, version=14.32.31326.0
    msvcp140_2.dll                                           .\msvcp140_2.dll, version=14.32.31326.0
    msvcp140_codecvt_ids.dll                                 .\msvcp140_codecvt_ids.dll, version=14.32.31326.0
    vcomp140.dll                                             .\vcomp140.dll, version=14.32.31326.0
    ijwhost.dll                                              .\ijwhost.dll, version=6,0,522,21309 @Commit: 70ae3df4a6f3c92fb6b315afc405edd10ff38579
    PaintDotNet.SystemLayer.Native.x64.dll                   .\PaintDotNet.SystemLayer.Native.x64.dll, version=4.311.8179.42221
    PROPSYS.dll                                              C:\Windows\SYSTEM32\PROPSYS.dll, version=7.0.19041.1 (WinBuild.160101.0800)
    gdiplus.dll                                              C:\Windows\WinSxS\amd64_microsoft.windows.gdiplus_6595b64144ccf1df_1.1.19041.1645_none_91a2a668cc89980b\gdiplus.dll, version=10.0.19041.1645 (WinBuild.160101.0800)
    WindowsCodecs.dll                                        C:\Windows\SYSTEM32\WindowsCodecs.dll, version=10.0.19041.1151 (WinBuild.160101.0800)
    bcrypt.dll                                               C:\Windows\System32\bcrypt.dll, version=10.0.19041.1 (WinBuild.160101.0800)
    System.Threading.dll                                     .\System.Threading.dll, version=6.0.522.21309
    System.Runtime.Extensions.dll                            .\System.Runtime.Extensions.dll, version=6.0.522.21309
    System.Runtime.CompilerServices.VisualC.dll              .\System.Runtime.CompilerServices.VisualC.dll, version=6.0.522.21309
    System.Collections.NonGeneric.dll                        .\System.Collections.NonGeneric.dll, version=6.0.522.21309
    System.Runtime.Intrinsics.dll                            .\System.Runtime.Intrinsics.dll, version=6.0.522.21309
    windows.storage.dll                                      C:\Windows\SYSTEM32\windows.storage.dll, version=10.0.19041.1 (WinBuild.160101.0800)
    Wldp.dll                                                 C:\Windows\SYSTEM32\Wldp.dll, version=10.0.19041.1 (WinBuild.160101.0800)
    SHCORE.dll                                               C:\Windows\System32\SHCORE.dll, version=10.0.19041.1 (WinBuild.160101.0800)
    shlwapi.dll                                              C:\Windows\System32\shlwapi.dll, version=10.0.19041.1 (WinBuild.160101.0800)
    PaintDotNet.Core.dll                                     .\PaintDotNet.Core.dll, version=4.311.8179.42221
    System.Private.Uri.dll                                   .\System.Private.Uri.dll, version=6.0.522.21309
    System.ComponentModel.Primitives.dll                     .\System.ComponentModel.Primitives.dll, version=6.0.522.21309
    System.Windows.Forms.Primitives.dll                      .\System.Windows.Forms.Primitives.dll, version=6.0.422.16407
    WindowsBase.dll                                          .\WindowsBase.dll, version=6.0.522.21509
    System.Drawing.Primitives.dll                            .\System.Drawing.Primitives.dll, version=6.0.522.21309
    PresentationFramework.dll                                .\PresentationFramework.dll, version=6.0.522.21509
    System.Xaml.dll                                          .\System.Xaml.dll, version=6.0.522.21509
    System.ComponentModel.dll                                .\System.ComponentModel.dll, version=6.0.522.21309
    System.Diagnostics.TraceSource.dll                       .\System.Diagnostics.TraceSource.dll, version=6.0.522.21309
    System.Collections.dll                                   .\System.Collections.dll, version=6.0.522.21309
    System.Threading.Thread.dll                              .\System.Threading.Thread.dll, version=6.0.522.21309
    System.Text.Encoding.CodePages.dll                       .\System.Text.Encoding.CodePages.dll, version=6.0.522.21309
    PaintDotNet.Resources.dll                                .\PaintDotNet.Resources.dll, version=4.311.8179.42221
    Newtonsoft.Json.dll                                      .\Newtonsoft.Json.dll, version=13.0.1.25517
    Microsoft.Win32.Primitives.dll                           .\Microsoft.Win32.Primitives.dll, version=6.0.522.21309
    System.Linq.Expressions.dll                              .\System.Linq.Expressions.dll, version=6.0.522.21309
    System.ComponentModel.TypeConverter.dll                  .\System.ComponentModel.TypeConverter.dll, version=6.0.522.21309
    System.ObjectModel.dll                                   .\System.ObjectModel.dll, version=6.0.522.21309
    System.Runtime.Numerics.dll                              .\System.Runtime.Numerics.dll, version=6.0.522.21309
    PresentationNative_cor3.dll                              .\PresentationNative_cor3.dll, version=6,0,22,21304 @Commit: 3510f88911e3fea61a4eeb481d7a1fbae9795c7b
    PaintDotNet.Data.dll                                     .\PaintDotNet.Data.dll, version=4.311.8179.42221
    System.Configuration.ConfigurationManager.dll            .\System.Configuration.ConfigurationManager.dll, version=6.0.422.16404
    System.Collections.Specialized.dll                       .\System.Collections.Specialized.dll, version=6.0.522.21309
    System.Xml.ReaderWriter.dll                              .\System.Xml.ReaderWriter.dll, version=6.0.522.21309
    System.Private.Xml.dll                                   .\System.Private.Xml.dll, version=6.0.522.21309
    PaintDotNet.Framework.dll                                .\PaintDotNet.Framework.dll, version=4.311.8179.42221
    System.Net.WebClient.dll                                 .\System.Net.WebClient.dll, version=6.0.522.21309
    System.ComponentModel.EventBasedAsync.dll                .\System.ComponentModel.EventBasedAsync.dll, version=6.0.522.21309
    System.Memory.dll                                        .\System.Memory.dll, version=6.0.522.21309
    System.Text.Encoding.Extensions.dll                      .\System.Text.Encoding.Extensions.dll, version=6.0.522.21309
    System.Collections.Immutable.dll                         .\System.Collections.Immutable.dll, version=6.0.522.21309
    Microsoft.Win32.SystemEvents.dll                         .\Microsoft.Win32.SystemEvents.dll, version=6.0.422.16404
    System.Threading.ThreadPool.dll                          .\System.Threading.ThreadPool.dll, version=6.0.522.21309
    System.Drawing.Common.dll                                .\System.Drawing.Common.dll, version=6.0.422.16404
    Microsoft.Win32.Registry.dll                             .\Microsoft.Win32.Registry.dll, version=6.0.522.21309
    System.Linq.dll                                          .\System.Linq.dll, version=6.0.522.21309
    dxgi.dll                                                 C:\Windows\SYSTEM32\dxgi.dll, version=10.0.19041.1566 (WinBuild.160101.0800)
    MSCTF.dll                                                C:\Windows\System32\MSCTF.dll, version=10.0.19041.1 (WinBuild.160101.0800)
    PresentationCore.dll                                     .\PresentationCore.dll, version=6.0.522.21509
    DirectWriteForwarder.dll                                 .\DirectWriteForwarder.dll, version=6,0,522,21509 @Commit: 14bf2e54800ba75bfd06cbb4f2e470cbfffc9a5b
    System.Diagnostics.Debug.dll                             .\System.Diagnostics.Debug.dll, version=6.0.522.21309
    dwrite.dll                                               C:\Windows\SYSTEM32\dwrite.dll, version=10.0.19041.1 (WinBuild.160101.0800)
    UIAutomationTypes.dll                                    .\UIAutomationTypes.dll, version=6.0.522.21509
    Accessibility.dll                                        .\Accessibility.dll, version=6.0.422.16407
    System.Numerics.Vectors.dll                              .\System.Numerics.Vectors.dll, version=6.0.522.21309
    clbcatq.dll                                              C:\Windows\System32\clbcatq.dll, version=2001.12.10941.16384 (WinBuild.160101.0800)
    System.IO.Packaging.dll                                  .\System.IO.Packaging.dll, version=6.0.422.16404
    UIAnimation.dll                                          C:\Windows\System32\UIAnimation.dll, version=10.0.19041.746 (WinBuild.160101.0800)
    System.Diagnostics.FileVersionInfo.dll                   .\System.Diagnostics.FileVersionInfo.dll, version=6.0.522.21309
    version.dll                                              C:\Windows\SYSTEM32\version.dll, version=10.0.19041.546 (WinBuild.160101.0800)
    PaintDotNet.Effects.dll                                  .\PaintDotNet.Effects.dll, version=4.311.8179.42221
    System.Threading.Tasks.Parallel.dll                      .\System.Threading.Tasks.Parallel.dll, version=6.0.522.21309
    System.Runtime.CompilerServices.Unsafe.dll               .\System.Runtime.CompilerServices.Unsafe.dll, version=6.0.522.21309
    comctl32.dll                                             C:\Windows\WinSxS\amd64_microsoft.windows.common-controls_6595b64144ccf1df_6.0.19041.1110_none_60b5254171f9507e\comctl32.dll, version=6.10 (WinBuild.160101.0800)
    mfplat.dll                                               C:\Windows\SYSTEM32\mfplat.dll, version=10.0.19041.1 (WinBuild.160101.0800)
    cfgmgr32.dll                                             C:\Windows\System32\cfgmgr32.dll, version=10.0.19041.1620 (WinBuild.160101.0800)
    RTWorkQ.DLL                                              C:\Windows\SYSTEM32\RTWorkQ.DLL, version=10.0.19041.1 (WinBuild.160101.0800)
    CompPkgSup.DLL                                           C:\Windows\SYSTEM32\CompPkgSup.DLL, version=10.0.19041.746 (WinBuild.160101.0800)
    Windows.StateRepositoryPS.dll                            C:\Windows\System32\Windows.StateRepositoryPS.dll, version=10.0.19041.1466 (WinBuild.160101.0800)
    ucrtbase.dll                                             .\ucrtbase.dll, version=10.0.22000.194 (WinBuild.160101.0800)
    System.Runtime.Loader.dll                                .\System.Runtime.Loader.dll, version=6.0.522.21309
    WebPFileType.dll                                         .\Bundled\WebPFileType\WebPFileType.dll, version=1.3.12.0
    AvifFileType.dll                                         .\Bundled\AvifFileType\AvifFileType.dll, version=1.1.19.0
    DdsFileTypePlus.dll                                      .\Bundled\DDSFileTypePlus\DdsFileTypePlus.dll, version=1.10.12.0
    TextShaping.dll                                          C:\Windows\SYSTEM32\TextShaping.dll, version=
    WinTypes.dll                                             C:\Windows\System32\WinTypes.dll, version=10.0.19041.1320 (WinBuild.160101.0800)
    System.Diagnostics.Tracing.dll                           .\System.Diagnostics.Tracing.dll, version=6.0.522.21309
    d2d1.dll                                                 C:\Windows\SYSTEM32\d2d1.dll, version=10.0.19041.1 (WinBuild.160101.0800)
    wtsapi32.dll                                             C:\Windows\SYSTEM32\wtsapi32.dll, version=10.0.19041.546 (WinBuild.160101.0800)
    WINSTA.dll                                               C:\Windows\SYSTEM32\WINSTA.dll, version=10.0.19041.546 (WinBuild.160101.0800)
    d3d11.dll                                                C:\Windows\SYSTEM32\d3d11.dll, version=10.0.19041.1620 (WinBuild.160101.0800)
    D3D10Warp.dll                                            C:\Windows\SYSTEM32\D3D10Warp.dll, version=10.0.19041.546 (WinBuild.160101.0800)
    dxcore.dll                                               C:\Windows\SYSTEM32\dxcore.dll, version=10.0.19041.546 (WinBuild.160101.0800)
    UIAutomationCore.dll                                     C:\Windows\SYSTEM32\UIAutomationCore.dll, version=7.2.19041.1 (WinBuild.160101.0800)
    sxs.dll                                                  C:\Windows\SYSTEM32\sxs.dll, version=10.0.19041.1 (WinBuild.160101.0800)
    System.Reflection.MetadataLoadContext.dll                .\System.Reflection.MetadataLoadContext.dll, version=6.0.21.52210
    System.Reflection.Metadata.dll                           .\System.Reflection.Metadata.dll, version=6.0.522.21309
    System.IO.MemoryMappedFiles.dll                          .\System.IO.MemoryMappedFiles.dll, version=6.0.522.21309
    DynamicDraw.dll                                          .\Effects\DynamicDraw\DynamicDraw.dll, version=3.3.0
    System.Resources.Extensions.dll                          .\System.Resources.Extensions.dll, version=6.0.422.16404
    System.Drawing.dll                                       .\System.Drawing.dll, version=6.0.422.16407
    System.Runtime.Serialization.Formatters.dll              .\System.Runtime.Serialization.Formatters.dll, version=6.0.522.21309
    mscorlib.dll                                             .\mscorlib.dll, version=6.0.522.21309
    System.Security.Claims.dll                               .\System.Security.Claims.dll, version=6.0.522.21309
    System.CodeDom.dll                                       .\System.CodeDom.dll, version=6.0.422.16404
    dwmapi.DLL                                               C:\Windows\SYSTEM32\dwmapi.DLL, version=10.0.19041.1 (WinBuild.160101.0800)
    dataexchange.dll                                         C:\Windows\system32\dataexchange.dll, version=10.0.19041.1387 (WinBuild.160101.0800)
    dcomp.dll                                                C:\Windows\system32\dcomp.dll, version=10.0.19041.1566 (WinBuild.160101.0800)
    twinapi.appcore.dll                                      C:\Windows\system32\twinapi.appcore.dll, version=10.0.19041.1 (WinBuild.160101.0800)
    textinputframework.dll                                   C:\Windows\SYSTEM32\textinputframework.dll, version=10.0.19041.1620 (WinBuild.160101.0800)
    CoreUIComponents.dll                                     C:\Windows\System32\CoreUIComponents.dll, version=10.0.19041.546
    CoreMessaging.dll                                        C:\Windows\System32\CoreMessaging.dll, version=10.0.19041.746
    WS2_32.dll                                               C:\Windows\System32\WS2_32.dll, version=10.0.19041.1081 (WinBuild.160101.0800)
    ntmarta.dll                                              C:\Windows\SYSTEM32\ntmarta.dll, version=10.0.19041.1 (WinBuild.160101.0800)
    powrprof.dll                                             C:\Windows\SYSTEM32\powrprof.dll, version=10.0.19041.1 (WinBuild.160101.0800)
    UMPDC.dll                                                C:\Windows\SYSTEM32\UMPDC.dll, version=
    System.Text.RegularExpressions.dll                       .\System.Text.RegularExpressions.dll, version=6.0.522.21309
    oleacc.dll                                               C:\Windows\SYSTEM32\oleacc.dll, version=7.2.19041.746 (WinBuild.160101.0800)
    System.Private.Xml.Linq.dll                              .\System.Private.Xml.Linq.dll, version=6.0.522.21309
    System.Xml.XDocument.dll                                 .\System.Xml.XDocument.dll, version=6.0.522.21309
    winmm.DLL                                                C:\Windows\SYSTEM32\winmm.DLL, version=10.0.19041.1 (WinBuild.160101.0800)
    policymanager.dll                                        C:\Windows\SYSTEM32\policymanager.dll, version=10.0.19041.1620 (WinBuild.160101.0800)
    msvcp110_win.dll                                         C:\Windows\SYSTEM32\msvcp110_win.dll, version=10.0.19041.546 (WinBuild.160101.0800)
    System.IO.Compression.dll                                .\System.IO.Compression.dll, version=6.0.522.21309
    System.Runtime.Serialization.Primitives.dll              .\System.Runtime.Serialization.Primitives.dll, version=6.0.522.21309
    System.Console.dll                                       .\System.Console.dll, version=6.0.522.21309
    Microsoft.DiaSymReader.Native.amd64.dll                  .\Microsoft.DiaSymReader.Native.amd64.dll, version=14.28.29715.1 built by: vcwrkspc
    System.Diagnostics.StackTrace.dll                        .\System.Diagnostics.StackTrace.dll, version=6.0.522.21309
    explorerframe.dll                                        C:\Windows\system32\explorerframe.dll, version=10.0.19041.1 (WinBuild.160101.0800)
    PresentationFramework-SystemXmlLinq.dll                  .\PresentationFramework-SystemXmlLinq.dll, version=6.0.522.21509
    System.Xml.Linq.dll                                      .\System.Xml.Linq.dll, version=6.0.522.21309
    igd10iumd64.dll                                          C:\Windows\System32\DriverStore\FileRepository\iigd_dch.inf_amd64_a634af1513618033\igd10iumd64.dll, version=27.20.100.8729
    ncrypt.dll                                               C:\Windows\SYSTEM32\ncrypt.dll, version=10.0.19041.1 (WinBuild.160101.0800)
    NTASN1.dll                                               C:\Windows\SYSTEM32\NTASN1.dll, version=10.0.19041.1 (WinBuild.160101.0800)
    igdgmm64.dll                                             C:\Windows\System32\DriverStore\FileRepository\iigd_dch.inf_amd64_a634af1513618033\igdgmm64.dll, version=27.20.100.8729
    igc64.dll                                                C:\Windows\System32\DriverStore\FileRepository\iigd_dch.inf_amd64_a634af1513618033\igc64.dll, version=27.20.100.8729
    setupapi.DLL                                             C:\Windows\System32\setupapi.DLL, version=10.0.19041.1 (WinBuild.160101.0800)
    DEVOBJ.dll                                               C:\Windows\SYSTEM32\DEVOBJ.dll, version=10.0.19041.1620 (WinBuild.160101.0800)
    WINTRUST.dll                                             C:\Windows\System32\WINTRUST.dll, version=10.0.19041.1566 (WinBuild.160101.0800)
    CRYPT32.dll                                              C:\Windows\System32\CRYPT32.dll, version=10.0.19041.1 (WinBuild.160101.0800)
    MSASN1.dll                                               C:\Windows\SYSTEM32\MSASN1.dll, version=10.0.19041.546 (WinBuild.160101.0800)

Let me know anything to try.

Edit: Delay is not tied to image size, even a 1x1 image takes almost ten seconds. I can see the preview of it immediately, and then the program is paused doing who-knows-what for the same duration

[Rick Brewster]

What if you disable your antivirus? We've seen some pretty nasty lag/delays caused by AV (even Windows Defender)

[NinthDesertDude]

33 minutes ago, Rick Brewster said:

What if you disable your antivirus?

I've only got Windows Defender installed; turning it off and restarting didn't resolve it either. I decided to double-check 4.3.10 again and it repros there, so I guess it can be chalked up squarely to some issue with my computer. Maybe some updates are out of date (or the computer just decided this is how it'll go about aging, since I know my hard drive is clicking and will die eventually)

[BoltBait]

27 minutes ago, NinthDesertDude said:

I know my hard drive is clicking and will die eventually

 

It is dying now.

 

BACKUP ALL OF YOUR FILES RIGHT NOW!!!!

[Rick Brewster]

Yeah this sounds like it's your hard drive. Act immediately.

[NinthDesertDude]

Yep, thanks for the concern. I have nothing important on this computer right now. I'm just using it to program and push updates to Github so nothing important sits around.

[NinthDesertDude]

Finally narrowed this one down by accident. This only repros with the portable version of paint.net. I uninstalled PDN and dragged the files from the portable version to an empty paint.net folder in the normal location, then after that images were suddenly taking up to 10 seconds again like this post describes. I just removed that and reinstalled via the normal setup and it works.

Now I wonder if anyone else can repro the issue in the current portable version of paint.net.

[Rick Brewster]

Okay there's a few more things you can try.

 

1. Does this also happen with the 5.0 Beta? (it probably does, but worth checking)

2. Make sure to extract the portable version to its own folder (like on the Desktop or in Downloads or some temp directory), don't just copy it on top of an actual installation. 

3. Rename PaintDotNet.Configuration.json to something else like PaintDotNet.Configuration.json.bak -- does the problem persist? This file only contains one little option that turns on portable mode. Renaming/deleting the file turns it back into a "normal" copy of Paint.NET (albeit not "installed").