webstorage too unstable for filterlists Rated 4 out of 5 stars

ever since the migration to webStorage my filters keep disappearing after a few browser restarts, so I think it's better to keep the old storage system as (at least) a backup until webStorage has become stable/reliable. (and please let us make 2.8.* compatible backups (including the subscriptions) so that we don't have to start the whole shebang of recreating every filter we use if we decide to revert to a stable version)