If Visual Studio 2017 is currently installed and the preview version is installed alongside it, Setting Editor Preferences>Source Control>Source Code Editor to Visual Studio 2017 will always open the Preview version of VS.
Additionally, if the preview is later uninstalled, the editor will only open VS2015, even if Source Code Editor is set to Visual Studio 2017. Locally this also caused the VS2015 splash to not display properly when opening.
If the preview is installed, the editor will always open the preview over the release. If the preview version is uninstalled, 2015 will launch instead of 2017
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