Rendered whitespace in selection hard to read

When displaying whitespace characters in the selected code via editor.renderWhitespace: selection (which is the new default, by the way), the characters are hard to see. Pictured here is Python source code.

Dracula:

Dracula Soft:

Not sure how feasible it would be to update editorWhitespace.foreground to add some contrast without it looking ugly when unselected.

[leandrocunha]

I opened a PR for this improvement, really useful suggestion

[beeb]

Additional option: use transparency, for instance #ffffff1f which gives this:

To be honest this gives very good readability both in selected and unselected state.