Allow diff between current open file's changes and the saved original

[ahtcx]

Sometimes I forget what changes I've done between saves and that would be a useful feature.

[vscodebot]

(Experimental duplicate detection)
Thanks for submitting this issue. Please also check if it is already covered by an existing one, like:

• Spinner or indicator while saving (#22162)

[kieferrm]

/duplicate of #26339

[vscodebot]

Thanks for creating this issue! We figured it's covering the same as another one we already have. Thus, we closed this one as a duplicate. You can search for existing issues here. See also our issue reporting guidelines.

Happy Coding!