2024-11-16

Compatibility Administrator notes
- Links
  - The Real Shim Shady
  - Windows Confidential: A Trip Down Memory Lane with EmulateHeap
  - [Known Compatibility Fixes, Compatibility Modes, and AppHelp Messages](https://learn.microsoft.com/en-us/previous-versions/windows/it-pro/windows-7/cc765984(v=ws.10)
  - Persist It: Using and Abusing Microsoft Fix It Patches
    - Explains why some applications have no visible fixes - CompatAdmin doesn't support showing in-memory patches, so it looks like some applications have no associated fixes
  - Windows 0wn3d By Default
- Utilities
  - sdb2xml
  - sdb-explorer
- Built-in SDB files in C:\Windows\System32\apppatch\
  - When I try to load {drvmain,sysmain,msimain}.sdb it fails with "This is a system compatibility database"
    - I think this means that it's already included in the list?
  - shellFeatureInbox.sdb (Microsoft Windows Shell Feature Compatibility Database")
    - Has some Microsoft apps none of them show any fixes applied?
    - It does say "Application: "X" contains 1 fix(es)" in the bottom though
      - I think this is just the number of programs
  - pcamain.sdb (Microsoft Windows Program Compatibility Assistant Database)
    - Has 89 applications, no visible fixes
    - Probably related to this: https://techcommunity.microsoft.com/blog/askperf/the-program-compatibility-assistant---part-one/372538
      - But the Program Compatibility Assistant was only available for versions before Windows 7 - why is it still here?
  - frxmain.sdb (Microsoft Windows Program Frameworks and Dependencies Database)
    - 5 applications (Java, OpenSSL, Visual Basic, Visual C++ .NET Runtime, Visual C++ Runtime)
    - Java application is super broad, matches any file named java{,w,ws}.exe
    - No visible fixes
  - DirectXApps.sdb/DirectXApps_FOD.sdb (Microsoft Windows Graphics Database)
    - Has 4319/4177 applications, looks like mostly games
    - No visible fixes
- ReactOS has a AppCompat impl, should look at that
Made a simple thingie to run JS and show the result: https://sm4.ca/js