On my iPhone6 it’s 1.1Gigs. What really stinks is that I hadn’t done an update in over a year (it’s a real hassle for me), but just last week I finally broke down and did an update to the 9.3.5, and NOW they come out with this. Ugh.
One thing I do not like that changed when I did the update was that one can no longer clear the search history right in Safari. It seems that to clear the search history one needs to go into settings and it also clears all web data, which has the effect of signing out of websites. Maybe this new version will change that back, but it may be months before I decide to do an update again.
It's necessary. The reason for that is to clear those phishing and ransom ware websites that won't let go of your browser. If clearing history doesn't close the website and web data, then they reopen and you are back to having your browser hijacked all over again.