[EXTERNAL] Changing cell type doesn't work

[jonsequitur]

If you create a cell in one language, then use the language switcher to choose a different language, the submission is still treated as the original language.

[darranhayes]

VS Code insiders: 1.50.0-insider
Commit: bc38b0
DotNet Interactive Notebooks extension Git SHA ee0c261

Failing to execute FSharp for me. Also, a cell configured for FSharp when saved, closed, reopened, appears as a CSharp cell instead.

It really thinks it's CSharp:

FSharp cell rendered as CSharp after save, close, open: