The just-out IntelliJ IDEA 2017.1.2 update brings important bugfixes and overall improvements.
Among notable changes:
JUnit 5 M4 support (incl. running parametrized tests)
Support for the new Typescript 2.3 language features (e.g. for await)
An important fix for the freeze while editing Gradle build files
For the complete list of changes, see the release notes.
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UPDATE: If you download Windows ".zip" bundle, Kaspersky and some other antiviruses may flag "jre32\bin\unpack200.exe"