Fix wrong cursor positon (#4074)

Fixes #3713 , hopefully.
This happened when you were editing a file in two splits at once. An edit in one split that affected the cursor position in the other split would trigger an extra `onDidChangeTextEditorSelection` event that we should be ignoring.

extension.ts

@@ -263,6 +263,12 @@ export async function activate(context: vscode.ExtensionContext) {
 
  const mh = await getAndUpdateModeHandler();
 
+ // We may receive changes from other panels when, having selections in them containing the same file
+ // and changing text before the selection in current panel.
+ if (e.textEditor !== mh.vimState.editor) {
+ return;
+ }
+
  if (mh.vimState.focusChanged) {
  mh.vimState.focusChanged = false;
  return;