Why Resharper does not show up in Extension Manager in VS 2012
I am working on a VS extension which is somewhat like a subset of Resharper and was wondering why it does not show up in VS Extension Manager even though the manifest file is in the standard Extensions directory of VS. Looking at the manifest file, I can see that its MEFComponents are being loaded from the Resharper installation directory (my default: C:\Program Files(x86)...) but shouldn't it still be an "extension"?
They install their extensions via an .msi-based install, not a .vsix-based install, so there's no requirement their extension is listed there. They probably chose not to list it as is custom for .msi-installed things, since you have to remove it through the Windows control panel anyways.
Put another way, there's multiple ways to get yourself registered with Visual Studio, but not all of them actually puts an entry into the extension manager. They went with a way that doesn't, and it's nothing to be confused about.