macOS Sierra was released by Apple in September 2016. Java is compatible with this version, however, few Java issues have been reported on Sierra. We are actively working on identifying and resolving those issues.
A few of the issues that we are currently addressing are listed below.
On macOS Sierra 10.12, if a user presses modifier keys (such as Command, Alt, Shift) while an applet is running in a browser, an error box named “Internal Error” might be displayed. It will also show the “exec” icon in the macOS dock. The user can dismiss the applet, or try to rerun the applet while not pressing a modifier key. See JDK-8165867.
A bug in macOS Sierra has caused scrolling with the trackpad to to be very fast. A workaround is using a mouse, or updating to Java version 8 Update 121 (released January 2017) or later versions.
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