IDEA freezes due to large JavaScript source maps or debugger didn't work

Problem

When using IntelliJ IDEA (Ultimate Edition) on Windows 11, the IDE instances were frequently freezing, becoming unresponsive, and preventing any interaction such as selecting menus or text.

if the sourcemap size exceeds 20 Mb, com.intellij.openapi.util.io.FileTooBigException is thrown, breakpoints are not hit.

com.intellij.openapi.util.io.FileTooBigException: C:/views/git/sem/sem/jsclient/deploy/dist/vendor.js.map
at com.intellij.openapi.vfs.newvfs.impl.VirtualFileImpl.checkNotTooLarge(VirtualFileImpl.java:205)
at com.intellij.openapi.vfs.newvfs.impl.VirtualFileImpl.contentsToByteArray(VirtualFileImpl.java:123)
at com.intellij.openapi.vfs.newvfs.impl.VirtualFileImpl.contentsToByteArray(VirtualFileImpl.java:118)
at com.intellij.javascript.debugger.FileResolverByContentKt.selectMostSimilarFile(fileResolverByContent.kt:127)
at com.intellij.javascript.debugger.FileResolverByContentKt.resolveFileBySourceUrl(fileResolverByContent.kt:56)
at com.intellij.javascript.debugger.JSCachingFileFinder$findFile$2.invoke(JSCachingFileFinder.kt:30)
at com.intellij.javascript.debugger.JSCachingFileFinder$findFile$2.invoke(JSCachingFileFinder.kt:26)
at com.intellij.javascript.debugger.locationResolving.JSFileUrlMappings.findFile(JSFileUrlMappings.kt:38)
at com.intellij.javascript.debugger.JSCachingFileFinder.findFile(JSCachingFileFinder.kt:26)
at com.intellij.javascript.debugger.sourcemap.SourceMapLoaderKt.findSourceMap$findFile(SourceMapLoader.kt:155)
at com.intellij.javascript.debugger.sourcemap.SourceMapLoaderKt.findSourceMap(SourceMapLoader.kt:178)
at com.intellij.javascript.debugger.JavaScriptDebugProcess.findSourceMapBeforeAdd(JavaScriptDebugProcess.kt:939)
at com.intellij.javascript.debugger.JavaScriptDebugProcess$MyDebugEventListener.scriptAdded(JavaScriptDebugProcess.kt:701)
at jdk.internal.reflect.GeneratedMethodAccessor657.invoke(Unknown Source)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:568)
at com.intellij.util.EventDispatcher.dispatchVoidMethod(EventDispatcher.java:120)

Cause

The issue was caused by the debugger attempting to load large source maps that exceeded 20 MB in size, which exceeded the default content size limit in the IDE configuration.

Resolution

To resolve this issue, the following configuration change was applied:

1. Open IntelliJ IDEA.
2. Navigate to Help > Edit Custom VM Options from the menu.
3. Add the property -Didea.max.content.load.filesize=100000 to increase the maximum allowable content load size (measured in kilobytes).
4. Save the changes and restart the IDE.

Following these steps resolved the problem, preventing the application from freezing and restoring debugging functionality. For updates on this issue, users can follow the YouTrack issue WEB-60422.