IntelliJ Update To 9.0.3 Flex Namespace Error
If your running into error with IntelliJ IDEA after upgrading to 9.0.3 you may want to try the tip below:
If you just upgraded from 9.0.2 to 9.0.3 you may want to invalidate your caches (File > Invalidate Caches … then restart IDEA). There was a change along the way to the Flex support that caused old indexes/caches to not work for some people. That resulted in most of the core Flex code to show as errors, and would break code completion. Error highlighting and code completion depend on the indexes created in the IDEA cache. After invalidating the caches and restarting, IDEA will need to re-index your project at startup.
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