Apple quashes bugs in iOS, macOS and Safari

Apple on Monday updated macOS Sierra to 10.12.3, patching 11 security vulnerabilities and addressing a graphics hardware problem in the latest 15-in. MacBook Pro laptop.
At the same time, Apple released iOS 10.2.1, an update that fixed 18 security flaws, the bulk of them in WebKit, the foundation of the baked-in Safari browser.
According to Apple's typically terse update documentation, macOS 10.12.3 "improves automatic graphics switching on MacBook Pro (15-in., October 2016)." Another fix addre