Ok, I have searched for days until I'm beyond my patience level. I have a Samsung Note 4. Several days ago I lost both my Facebook and Pinterest widgets. The widgets were black, said their was a problem, so I removed them from the screen, then went to my widgets to restore them, and they were gone. I fixed my Facebook widget issue after uninstalling updates, uninstalled Pinterest also, and set Google play to not auto update - because update is the issue. Every time it updates, the widget would vanish.
Well, I see everyone figured that out - search for Facebook widget gone (they won't let me post a link.. Wth).
At least one member mentioned also having a problem with the Pinterest widget, but no solution exists.
I uninstalled Pinterest, Facebook updates, and my launcher, then set touchwiz back to default launcher. I restarted my phone. Facebook widget returned, reinstalled Pinterest, but widget did not come back. Facebook updated, widget disappeared. Uninstalled, set to not auto update, restarted, reinstalled, Facebook back for good, Pinterest still missing. Removed all screens and items. Went through same process, no success. I'm at the end of ideas. I have the Pinterest app icon in app drawer, but the widget is still missing from my widgets.