OS:
DragonflyBSD
GNU/Hurd
GNU/Linux
FreeBSD
MS-DOS 6.11
OpenBSD
OpenSolaris
NetBSD
Plan9
Windows
Test:
Test float style:
Test: using value, but showing the label:
Empty value: use ""
No value attribute: just use label
data-value set: use 3
data-value set but empty: use ""
Value attribute set: use 4