Almost three years ago I created this request on Uservoice:
This request tries to solve a problem that is increasingly tricky: while Microsoft (or developers that work within Microsoft) release a new extension for each new Visual Studio version, most of us want desperately to update our existing extensions to support multiple versions of Visual Studio. Ideally we would like to have a single package DLL that targets many Visual Studio versions, but if you want to use the latest extensibility APIs, then most of the time you are forced to add references that demand a new package DLL because those references don’t exist on old versions of Visual Studio. But yet, we would like to ship those different package DLLs in the same unified VSIX file, so that for some versions of Visual Studio the VSIX file deploys a package DLL, and for other versions of Visual Studio the VSIX file deploys a different package DLL. Even you may want to deploy different .pkgdef files, as I explained in the request. And nowadays, with the release of Visual Studio 2017 and its manifest “v3”, we would like even different manifests (“v1” for Visual Studio 2010, “v3” for Visual Studio 2012-2017) within the same VSIX, which would solve the most common question on the forums these days: “How can I make a single VSIX that targets Visual Studio 2010-2017?” (sorry, you can’t).
Today, I have received an update from UserVoice indicating that Microsoft is now working on it, and that it will be “for a future servicing release of Visual Studio 2017”. Big news!!!
You can still vote for the idea to show user demand 🙂