It is important to distinguish EAP from traditional pre-release software. Please note that the quality of EAP versions may at times be way below even usual beta standards.

You can setup auto-update of Scala plugin EAP builds in IntelliJ IDEA.
Simply select desired update channel from a drop-down menu at "Updates" tab in Scala plugin settings page.

• SCL-9742 Play is not working in 2.0.228.6

• SCL-9742 Play is not working in 2.0.228.6

• SCL-9505 Some breakpoints in lambdas are never hit

• SCL-9475 error opening sbt project spoiwo: ;' expected but 'lazy' found.
• SCL-9605 formatting changes value of interpolated string literal
• SCL-8514 sbt plugin does not honor SBT_OPTS environment variable
• SCL-9597 Importing/opening a Gradle Scala project incorrectly configures the Scala compiler encoding setting

• SCL-9535 ClassCastException since IDEA 15 upgrade
• SCL-9445 SyntheticMembersInjector doesn't inject case class properly
• SCL-9490 ScalaDoc @throws exception class highlighted red if Exception is a case class
• SCL-9482 Autocomplete of @routes.Assets.at()
• SCL-9476 Creating a New Play 2.x Application Yields Useless Project
• SCL-9457 some types in decompiled classes from 2.12 M3 contains `<no symbol>`.`<root>` prefix

• SCL-9535 ClassCastException since IDEA 15 upgrade
• SCL-9476 Creating a New Play 2.x Application Yields Useless Project

• SCL-9436 Parser fails on snail operator @*
• SCL-9156 Reference searchers from Scala plugin are slow
• SCL-9504 Invalid range of TODO item
• SCL-9234 .idea/scala_compiler.xml gets corrupted during SBT refresh
• SCL-9501 Fatal Error reporter does not work with Scala plugin
• SCL-9455 Wrong inspection of DelayedInit for App trait
• SCL-9453 Error running play 2 project
• SCL-9480 Cannot disable the inspection `method XXX is never used` using a source code comment
• SCL-9460 Type error highlighted on a valid array of anonymous functions
• SCL-9419 Highlighting error for `import scala.scalajs.js.|`
• SCL-9039 Debugging inside `async` block of code
• SCL-9433 Good code red - Another v15 regression
• SCL-8970 no highlighting for extractor pattern in patten match
• SCL-9397 Code completion incorrect (cache invalidation problem?)

• SCL-9394 Scala good code red in v15 only
• SCL-9426 Good code red - Regression in v15

• SCL-9400 IntelliJ IDEA 15 Scala plugin 2.0.0 not recognizing a Scala class

• SCL-9343 IntelliJ highlights valid code as error in Scala Plugin 1.9.265

• SCL-9000 Method call returning tuple within an unapply definition incorrectly maps entire tuple to first captured val at call site rather than destructuring tuple, leaving all remaining captures undefined
• SCL-9244 Macro annotations on methods don't expand
• SCL-9240 Good code yellow: "Useless expression" flagged incorrectly
• SCL-9287 Missing specs2 and junit libraries in the dependencies of a new Play project
• SCL-9317 Mark expanded macro applications
• SCL-2066 Formatter incorrectly indents braces of methods and other blocks if they are configured to be on a new line.
• SCL-9235 Incorrect "Java accessor method called as empty-paren" with Java 8 Stream API
• SCL-9252 add quickfix for "Type annotation required" inspection
• SCL-9230 debugger trees: label don't changes from "Collecting data..." for vars
• SCL-9309 No warning for duplicate aliases
• SCL-9270 possibility to create and use variables in evaluate expression
• SCL-8959 Change "working directory" of scala compiler to match project home
• SCL-8866 Syntax highlighting issue with Java 8
• SCL-9124 Scala plugin shows too many duplicated classes in inheritors dialog
• SCL-9179 Make 'Enable optimize imports automatically' command not a top-most one
• SCL-9272 Labeled objects do not work in "Evaluate expression" if "Scala" is selected
• SCL-9294 With Scala plugin enabled, com.intellij.debugger.NoDataException is thrown while debugging
• SCL-9354 Scala plugin broken by Scala compiler sources
• SCL-9273 Hierarchy, Go to implementation, and implementation gutter icons are broken
• SCL-9290 NPE on running Play
• SCL-5771 Completion for generic mutable collection classes does not work correctly
• SCL-7178 Provide better error message, when two type have the same name
• SCL-9192 Expression of type BigDecimal doesn't conform to expected type BigDecimal
• SCL-8195 An ability to mark some imports as used (so they are not removed upon reformat)
• SCL-9312 OutOfMemoryError when import/refresh large sbt project
• SCL-8933 Good code red: Wrong type inference in for comprehension (inferes to Nothing)
• SCL-8800 Code highlighting is totally broken for simulacrum

• SCL-9124 Scala plugin shows too many duplicated classes in inheritors dialog

• SCL-9309 No warning for duplicate aliases
• SCL-9294 With Scala plugin enabled, com.intellij.debugger.NoDataException is thrown while debugging

• SCL-9287 Missing specs2 and junit libraries in the dependencies of a new Play project
• SCL-9290 NPE on running Play
• SCL-7178 Provide better error message, when two type have the same name
• SCL-8195 An ability to mark some imports as used (so they are not removed upon reformat)

• SCL-3151 widen selection should include XML attribute text, then attribute text with quotation marks
• SCL-9141 Debugger jumps around in match statement
• SCL-9000 Method call returning tuple within an unapply definition incorrectly maps entire tuple to first captured val at call site rather than destructuring tuple, leaving all remaining captures undefined
• SCL-9240 Good code yellow: "Useless expression" flagged incorrectly
• SCL-8819 className() and methodName() macros missing in live templates
• SCL-4346 scaladoc doc comment parser can't handle lines in code examples starting with ""
• SCL-4953 parameter info doesn't find apply method of compound type
• SCL-9157 Faster file type detection
• SCL-9175 ScalaDoc parsing fails with code block containing JSON
• SCL-9235 Incorrect "Java accessor method called as empty-paren" with Java 8 Stream API
• SCL-9252 add quickfix for "Type annotation required" inspection
• SCL-9230 debugger trees: label don't changes from "Collecting data..." for vars
• SCL-9270 possibility to create and use variables in evaluate expression
• SCL-2066 Formatter incorrectly indents braces of methods and other blocks if they are configured to be on a new line.
• SCL-9158 Scala getClassesByName takes too much in a project that has no Scala
• SCL-5437 Inspection idea: warn when selecting a 'val' from a DelayedInit subclass (e.g. App)
• SCL-8959 Change "working directory" of scala compiler to match project home
• SCL-8866 Syntax highlighting issue with Java 8
• SCL-9179 Make 'Enable optimize imports automatically' command not a top-most one
• SCL-9273 Hierarchy, Go to implementation, and implementation gutter icons are broken
• SCL-9272 Labeled objects do not work in "Evaluate expression" if "Scala" is selected
• SCL-7909 incorrect "unnecessary parentheses" hint in scala
• SCL-3520 Honour "skip simple getters" setting
• SCL-9191 Throwable on new Play project creation
• SCL-5771 Completion for generic mutable collection classes does not work correctly
• SCL-9192 Expression of type BigDecimal doesn't conform to expected type BigDecimal
• SCL-8933 Good code red: Wrong type inference in for comprehension (inferes to Nothing)
• SCL-8800 Code highlighting is totally broken for simulacrum
• SCL-4036 override annotator should report error when overriding a val with a def.
• SCL-8167 Perform eviction for dependencies when importing project

• SCL-3603 good code red
• SCL-9092 add "create case class" option to popup menu (alt+enter)
• SCL-7431 Play template variables that generate full HTML attributes marked as errors
• SCL-9096 Inner trait (ScalaTest): Errorneous 'Reference must be prefixed' warning
• SCL-3151 widen selection should include XML attribute text, then attribute text with quotation marks
• SCL-9147 Stuck in an infinite loop when trying to import a project
• SCL-9049 Scaladoc generates stub with return also when return type is Unit
• SCL-5099 Pattern variables in field declarations are highlighted as fields
• SCL-9045 Play Framework, Twirl: Syntax highlighting error. Assigning an expression to an html attribute.
• SCL-9046 Play Framework, Twirl: Syntax highlighting error.
• SCL-9102 Open in browser after compilation is not working
• SCL-9041 Good code red: SAM for Comparable doesn't work
• SCL-9121 Import statements in worksheet become duplicated in output
• SCL-4484 Mark "then" as deprecated
• SCL-9129 some files from scala library are decompiled as java in scala 2.12.0-M2
• SCL-8989 Unable to track types through Scala Graph nodes
• SCL-4085 For @scala.deprecated, show the message in the scaladoc popup
• SCL-8808 Scaladoc in same line with case class causes false error
• SCL-9124 Scala plugin shows too many duplicated classes in inheritors dialog
• SCL-4346 scaladoc doc comment parser can't handle lines in code examples starting with ""
• SCL-4953 parameter info doesn't find apply method of compound type
• SCL-4872 No sensor of a word beginning when wrapping symbols are inputted in docs
• SCL-9157 Faster file type detection
• SCL-9031 Inspection for mapping to unit values fires when mapping to function returning unit
• SCL-9175 ScalaDoc parsing fails with code block containing JSON
• SCL-9158 Scala getClassesByName takes too much in a project that has no Scala
• SCL-9159 Inefficient ScClsStubBuilder
• SCL-9086 Getting NullPointerException again and again
• SCL-9051 Cannot rename variable on twirl parameters
• SCL-8934 Code folding not persisted across restart
• SCL-9135 Generate property generates wrong name for a setter
• SCL-9015 Very usual situation, when class can't be resolved in evaluate expression
• SCL-9100 Create run configuration for Play pfoject
• SCL-9018 EAP Debugger do not respect breakpoints in tests
• SCL-8999 Feature needed for call-by-name value parameter error
• SCL-5437 Inspection idea: warn when selecting a 'val' from a DelayedInit subclass (e.g. App)
• SCL-8952 Duplicate configuration section
• SCL-8931 Good code red: SAM converted from method
• SCL-8486 Copy+paste loses formatting JS code in *.scala.html template
• SCL-8966 Scala worksheet doesn't work with backticks
• SCL-9128 Nested stateful monads inspection should be turned off by default
• SCL-9019 A jar dependency (httpcore 4.0.1) keeps being "detached" from its "library" in the IDEA project every time the Gradle project is refreshed
• SCL-9191 Throwable on new Play project creation
• SCL-9146 ScalaJS React <. broken in Intellij 15 EAP
• SCL-9044 SBT 0.13.9 not working with Intellij
• SCL-4407 Wrong warning with empty-paren Java accessor with overloaded methods
• SCL-8720 Scala Worksheet and Scratch file at the same time.
• SCL-9010 "Your IDEA is outdated to use with Scala plugin" message with reference to build already in use
• SCL-4036 override annotator should report error when overriding a val with a def.
• SCL-6738 Javascript formatting broken in Play Framework Scala Templates

• SCL-9147 Stuck in an infinite loop when trying to import a project
• SCL-7431 Play template variables that generate full HTML attributes marked as errors
• SCL-9159 Inefficient ScClsStubBuilder
• SCL-4484 Mark "then" as deprecated
• SCL-8989 Unable to track types through Scala Graph nodes
• SCL-8486 Copy+paste loses formatting JS code in *.scala.html template
• SCL-8966 Scala worksheet doesn't work with backticks
• SCL-9146 ScalaJS React <. broken in Intellij 15 EAP
• SCL-6738 Javascript formatting broken in Play Framework Scala Templates

• SCL-4085 For @scala.deprecated, show the message in the scaladoc popup
• SCL-9092 add "create case class" option to popup menu (alt+enter)
• SCL-3603 good code red
• SCL-9096 Inner trait (ScalaTest): Errorneous 'Reference must be prefixed' warning
• SCL-9121 Import statements in worksheet become duplicated in output
• SCL-9135 Generate property generates wrong name for a setter
• SCL-9124 Scala plugin shows too many duplicated classes in inheritors dialog
• SCL-9129 some files from scala library are decompiled as java in scala 2.12.0-M2
• SCL-4872 No sensor of a word beginning when wrapping symbols are inputted in docs
• SCL-9128 Nested stateful monads inspection should be turned off by default
• SCL-8720 Scala Worksheet and Scratch file at the same time.

• SCL-8808 Scaladoc in same line with case class causes false error
• SCL-9049 Scaladoc generates stub with return also when return type is Unit
• SCL-5099 Pattern variables in field declarations are highlighted as fields
• SCL-9100 Create run configuration for Play pfoject
• SCL-9046 Play Framework, Twirl: Syntax highlighting error.
• SCL-9102 Open in browser after compilation is not working
• SCL-9041 Good code red: SAM for Comparable doesn't work
• SCL-9086 Getting NullPointerException again and again
• SCL-9031 Inspection for mapping to unit values fires when mapping to function returning unit
• SCL-8934 Code folding not persisted across restart
• SCL-9051 Cannot rename variable on twirl parameters
• SCL-9045 Play Framework, Twirl: Syntax highlighting error. Assigning an expression to an html attribute.
• SCL-9018 EAP Debugger do not respect breakpoints in tests
• SCL-8931 Good code red: SAM converted from method
• SCL-9044 SBT 0.13.9 not working with Intellij
• SCL-4407 Wrong warning with empty-paren Java accessor with overloaded methods

• SCL-9031 Inspection for mapping to unit values fires when mapping to function returning unit
• SCL-9018 EAP Debugger do not respect breakpoints in tests

• SCL-8999 Feature needed for call-by-name value parameter error
• SCL-9015 Very usual situation, when class can't be resolved in evaluate expression
• SCL-9019 A jar dependency (httpcore 4.0.1) keeps being "detached" from its "library" in the IDEA project every time the Gradle project is refreshed
• SCL-8952 Duplicate configuration section

• SCL-8965 SBT import is still broken (two months already)
• SCL-8579 SBT import does not respect JDK deduced by sbt-structure 1.4.15
• SCL-8631 Type error not shown when type tooltip is enabled

• IDEA-142373 JavaTestFinders escape
• SCL-8908 Plugin version lost if switching update channel
• SCL-8917 Breakpoints in lambda sometimes trigger in a different source file
• SCL-8835 Inspection "Replace with .contains" does not work with Scala 2.10
• SCL-5367 Good code shows as red: Using Value Types from Java
• SCL-8920 New SAM inspection doesn't catch Callable
• SCL-8863 Good code red: @uncheckedVariance annotation
• SCL-8890 inspection access to first/last element by index
• SCL-8852 "Comparing unrelated types" inspections can be improved
• SCL-4625 Spurious error accessing a protected method within a java class
• SCL-8935 NPE at autocompletion
• SCL-8921 Don't truncate the logger message in org.jetbrains.jps.cmdline.BuildMain (line 405?)
• SCL-8793 Good code red: function resolves to a completely unrelated library
• SCL-7170 Good code red: underscore after a by-name parameter
• SCL-7885 Java editor doesn't recognize all exceptions marked with @throws in Scala code
• SCL-8157 Good code red: calling apply in implicitly converted object
• SCL-6140 Support Scala 2.11 SAM
• SCL-8162 Support Kind Projector

• SCL-8803 Error highlighted when using multiple constructors for covariant generics
• SCL-8803 Error highlighted when using multiple constructors for covariant generics
• SCL-8632 Import quick fix menu automatically open Exclude sub-menu