message: Disallow operator with mark across files with backtick
  Forgot this in
diff: @@ -639,6 +639,10 @@ class MarkMovement extends BaseMovement {
  }
  if (mark.isUppercaseMark && mark.editor !== undefined) {
  + if (vimState.recordedState.operator && mark.editor !== vimState.editor) {
  + // Operators don't work across files
  + throw VimError.fromCode(ErrorCode.MarkNotSet);
  + }
  await ensureEditorIsActive(mark.editor);
  }
  