Hazards are (1) user accidentally removing data they want when doing "clear browsing data", (2) Mobile Safari deleting data if you don't visit the site frequent

Hazards are (1) user accidentally removing data they want when doing "clear browsing data", (2) Mobile Safari deleting data if you don't visit the site frequently enough and (3) unanticipated future changes to browsers that make more problems like (2). Other than that, IME it works well.