Add virtual keyboard to Kiosk

[rgthomson]

Very new user. Want to add a virtual keyboard for a touch screen that pops up when a text box is clicked on; both Firefox and Chrome have add-ons which could work. But the browsers report that they cannot be installed because the needed file cannot be modified (which of course is right with a Kiosk). How then to incorporate into the image? A search on the site shows several have done this? Rich