Ctrl+Alt+C: cycle forward, Ctrl+Alt+X: cycle backward
1: 2: 3: A Button:
4:
Username: (Ctrl+Alt+U or Ctrl+Alt+N jumps here)
Password: (Ctrl+Alt+P or Ctrl+Alt+F jumps here)
Some radio controls:
7:
8: (not displayed)
9: (hidden)
10: (parent element not displayed)
11: (parent element hidden)
12: (parent of parent element not displayed)
13: (parent of parent element hidden)
14: (disabled text)
15: