UPDATE: the inline error feature got released as a separate extension available here:
C# Show Inline Errors
C# Var Type CodeLens
This extension enables the display of the inferred types of identifiers declared with the var keyword, similar to the CodeLens items.
This extension works with VS2019
You can change the text size and color of the type names, and disable the adornments.
When doing Drag&Drop inside an editor window into a line that has adornments, the Drag&Drop operation inserts the text at the beginning of that line. you then have to drag the text into the desired column. this is a known bug in VS that will hopefully be fixed with VS2019.
When changing the options, a refresh must occur in the editor for the changed otions to be respected (e.g. scroll)
improve icons for the extension and for the Command for enabling/disabling the adornments
exclude list e.g. for types or literals / identifier patterns ??
tagging var immediately after comments
set the default color of the adornment to the color the var keyword is drawn in.
change the options page category title to something common to all my extions. ideas welcome