When you click a file in Source Control, it should open untracked files and show diffs for changed files

[vscodenpa]

In the Source Control side panel, when you select a file, it automatically brings up a diff. For changed files, this is a very sensible default. For untracked files, this makes no sense because it compares against a blank file. You can click the Open File icon and it'll open the file instead, and you can make this the default by setting git.openDiffOnClick to false. But this just reverses the direction of the problem.

The most sensible default click behavior is this:

• Changed Files -> Open Diff
• Untracked Files -> Open File