• VSCode Version: 1.9.1
• OS Version: macOS Sierra 10.12.3

Steps to Reproduce:

1. Enable a code lens
2. Scroll down to a position where there is a code lens above the rendered lines
3. Disable the code lens

Result:
The code scrolls up a couple lines.

Expected:
Center line should stay centered.

I'm not sure this ever happens in VSCode proper, but embedding it on sourcegraph.com exhibits the issue. If you go here: https://sourcegraph.com/github.com/gorilla/mux/-/blob/mux.go#L52:74 and click the Show authors button a couple times it exhibited the issue before b86e321 was applied. That patch might be a starting point, but it probably needs additional checks.