In situations where the footer is a global navigation element, you may want it to appear fixed so it doesn't scroll out of view. It's also possible to make a fixed footer persistent so it appears to not move between page transitions. This can be accomplished by using the persistent footer feature included in jQuery Mobile.
To make a footer persistent between transitions, assign an id value to the persistentFooterId of all relevant pages and use the same id value for each. For example, by setting persistentFooterId to "myfooter" to the current page and the target page, the framework will keep the footer anchors in the same spot during the page animation. This effect will only work correctly if the footers are set to position="fixed" so they are in view during the transition.
Blank - the footer is not persistent.
Any string value.