I have a note 5 for two months. And usually when I'm on Internet, I used the stock browser than Chrome, because it's fast and the memory is small compare to Chrome. When I open the Internet, I will be directed to the Quick Access, it's the first page I see when I open the internet and by the default, there are already some saved websites like Wikipedia, Google, Yahoo and etc. But one day, the wikipedia Icon is disappear and I am NOT deleting it by accident, and I NEVER deleted or removed the Wikipedia from Quick Access, I let the things in the way they are and NEVER do anything with it. At first I thought it's because the signal or the app has some errors, then I cleared the data and cache, then disconnect my wi-fi. The Wikipedia Icon appeared but in grayed area, (that's same for another icon like google, yahoo and etc.) BUT when I re-connect to the Wi-Fi again, the Icon disappeared again. I already checked this with my friend's Note 5 to see if this problem is only on my phone or not. The I'm doing the same method I did to my phone by opening the stock browser, clearing data and cache, then disconnected the Internet and re-open the stock browser. It turns out the Wikipedia Icon in my friend's phone isn't disappearing and still there on its place. So, it seems the problems only persist in my Note 5, and maybe there's some bug inside My Phone but I don't know where and why? I already asked a help from the service center, but they are not helping at all and saying the phone is fine 
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