- submit button now resolved within the filled field's form first
  (document-wide query hit the header search form's identical
  button[type=submit] — clicked Search instead of Next)
- fill/checks/submit merged into one page-side step; checkbox ticking
  with label/name/id pattern filter (keep|remember|signed|记住)
- tab tracking by target id (open→use→close), immune to stale/concurrent
  same-site tabs; verification opens its own tab and closes it
- digitimes recipe: explicit Next button selector + keep-me-signed-in
  checkbox for long-lived session cookie