For Mac OS users, there is a system setting that may not allow you to tab onto several types of elements in a web page. To change this setting:
Period Time Wednesday
Hr 1 8:00-8:50 8:00-8:50
Hr 2 8:54-9:44 8:54-9:44
Grab & Go/HR 9:44-10:24 9:44-9:52
Hr 3 10:28-11:18 9:52-10:40
Hr 4 11:22-12:12 10:44-11:32
Hr 5 12:16-1:37 11:36-12:51
Hr 6 1:41-2:31 12:55-1:43
Hr 7 2:35-3:28 1:47-2:40