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:
Margrett W., Scott R., Cheyane P., Jewelly R., Rochelle S., Makalyn N., Jaeley W., Olivia G., Stormie B., James B., Ethan N., Micheal M., Lilly G., Autumn F, Ty G.