diff --git a/bench/src/main/scala/Benchmarks.scala b/bench/src/main/scala/Benchmarks.scala
index 51cd411cc13b..ccb778453d91 100644
--- a/bench/src/main/scala/Benchmarks.scala
+++ b/bench/src/main/scala/Benchmarks.scala
@@ -15,7 +15,7 @@ import org.openjdk.jmh.results.format._
 import java.util.concurrent.TimeUnit
 
 import java.io.{File, FileOutputStream, BufferedWriter, FileWriter}
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 import scala.io.Source
 import scala.util.Using
 
diff --git a/community-build/community-projects/http4s b/community-build/community-projects/http4s
index fc0a18dd0a80..6f22ebe18cd2 160000
--- a/community-build/community-projects/http4s
+++ b/community-build/community-projects/http4s
@@ -1 +1 @@
-Subproject commit fc0a18dd0a8091f0b2cdc87b58953e76efa47426
+Subproject commit 6f22ebe18cd262e58cf31c86448891d860b7a03b
diff --git a/community-build/src/scala/dotty/communitybuild/projects.scala b/community-build/src/scala/dotty/communitybuild/projects.scala
index dc8047a95935..4784daca6bb5 100644
--- a/community-build/src/scala/dotty/communitybuild/projects.scala
+++ b/community-build/src/scala/dotty/communitybuild/projects.scala
@@ -22,7 +22,7 @@ def log(msg: String) = println(Console.GREEN + msg + Console.RESET)
 
 /** Executes shell command, returns false in case of error. */
 def exec(projectDir: Path, binary: String, arguments: Seq[String], environment: Map[String, String]): Int =
-  import collection.JavaConverters._
+  import scala.jdk.CollectionConverters._
   val command = binary +: arguments
   log(command.mkString(" "))
   val builder = new ProcessBuilder(command: _*).directory(projectDir.toFile).inheritIO()
diff --git a/compiler/src/dotty/tools/backend/jvm/GenBCode.scala b/compiler/src/dotty/tools/backend/jvm/GenBCode.scala
index 6430575f304e..73e8fd9edb3b 100644
--- a/compiler/src/dotty/tools/backend/jvm/GenBCode.scala
+++ b/compiler/src/dotty/tools/backend/jvm/GenBCode.scala
@@ -8,7 +8,7 @@ import dotty.tools.dotc.ast.tpd
 import dotty.tools.dotc.core.Phases.Phase
 
 import scala.collection.mutable
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 import dotty.tools.dotc.transform.SymUtils._
 import dotty.tools.dotc.interfaces
 import dotty.tools.dotc.report
@@ -605,13 +605,13 @@ class GenBCodePipeline(val int: DottyBackendInterface, val primitives: DottyPrim
       // Statistics.stopTimer(BackendStats.bcodeWriteTimer, writeStart)
     catch
       case e: MethodTooLargeException =>
-        val method = 
+        val method =
           s"${e.getClassName.replaceAll("/", ".")}.${e.getMethodName}"
-        val msg = 
-          s"Generated bytecode for method '$method' is too large. Size: ${e.getCodeSize} bytes. Limit is 64KB" 
+        val msg =
+          s"Generated bytecode for method '$method' is too large. Size: ${e.getCodeSize} bytes. Limit is 64KB"
         report.error(msg)
       case e: ClassTooLargeException =>
-        val msg = 
+        val msg =
           s"Class '${e.getClassName.replaceAll("/", ".")}' is too large. Constant pool size: ${e.getConstantPoolCount}. Limit is 64K entries"
         report.error(msg)
 
diff --git a/compiler/src/dotty/tools/dotc/classpath/DirectoryClassPath.scala b/compiler/src/dotty/tools/dotc/classpath/DirectoryClassPath.scala
index 950f46678fc1..7f20d7c7d9ea 100644
--- a/compiler/src/dotty/tools/dotc/classpath/DirectoryClassPath.scala
+++ b/compiler/src/dotty/tools/dotc/classpath/DirectoryClassPath.scala
@@ -14,7 +14,7 @@ import dotty.tools.io.{AbstractFile, PlainFile, ClassPath, ClassRepresentation,
 import FileUtils._
 import PlainFile.toPlainFile
 
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 import scala.collection.immutable.ArraySeq
 import scala.util.control.NonFatal
 
diff --git a/compiler/src/dotty/tools/dotc/config/CommandLineParser.scala b/compiler/src/dotty/tools/dotc/config/CommandLineParser.scala
index f7c4b825c244..2bc8902c5de3 100644
--- a/compiler/src/dotty/tools/dotc/config/CommandLineParser.scala
+++ b/compiler/src/dotty/tools/dotc/config/CommandLineParser.scala
@@ -4,7 +4,7 @@ import scala.annotation.tailrec
 import scala.collection.mutable.ArrayBuffer
 import java.lang.Character.isWhitespace
 import java.nio.file.{Files, Paths}
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 /** A simple enough command line parser.
  */
diff --git a/compiler/src/dotty/tools/dotc/config/WrappedProperties.scala b/compiler/src/dotty/tools/dotc/config/WrappedProperties.scala
index 2e4ddff59059..5b79432a97e7 100644
--- a/compiler/src/dotty/tools/dotc/config/WrappedProperties.scala
+++ b/compiler/src/dotty/tools/dotc/config/WrappedProperties.scala
@@ -22,7 +22,7 @@ trait WrappedProperties extends PropertiesTrait {
   override def envOrNone(name: String): Option[String]       = wrap(super.envOrNone(name)).flatten
 
   def systemProperties: Iterator[(String, String)] = {
-    import scala.collection.JavaConverters._
+    import scala.jdk.CollectionConverters._
     wrap(System.getProperties.asScala.iterator) getOrElse Iterator.empty
   }
 }
diff --git a/compiler/src/dotty/tools/dotc/profile/Profiler.scala b/compiler/src/dotty/tools/dotc/profile/Profiler.scala
index ae86713a378c..6df88d9e28f0 100644
--- a/compiler/src/dotty/tools/dotc/profile/Profiler.scala
+++ b/compiler/src/dotty/tools/dotc/profile/Profiler.scala
@@ -81,7 +81,7 @@ private [profile] object NoOpProfiler extends Profiler {
   override def finished(): Unit = ()
 }
 private [profile] object RealProfiler {
-  import scala.collection.JavaConverters._
+  import scala.jdk.CollectionConverters._
   val runtimeMx: RuntimeMXBean = ManagementFactory.getRuntimeMXBean
   val memoryMx: MemoryMXBean = ManagementFactory.getMemoryMXBean
   val gcMx: List[GarbageCollectorMXBean] = ManagementFactory.getGarbageCollectorMXBeans.asScala.toList
diff --git a/compiler/src/dotty/tools/dotc/semanticdb/Tools.scala b/compiler/src/dotty/tools/dotc/semanticdb/Tools.scala
index b611de678c13..ffd156672cc6 100644
--- a/compiler/src/dotty/tools/dotc/semanticdb/Tools.scala
+++ b/compiler/src/dotty/tools/dotc/semanticdb/Tools.scala
@@ -2,7 +2,7 @@ package dotty.tools.dotc.semanticdb
 
 import java.nio.file._
 import java.nio.charset.StandardCharsets
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 import dotty.tools.dotc.util.SourceFile
 import dotty.tools.dotc.semanticdb.Scala3.given
 
diff --git a/compiler/src/dotty/tools/dotc/transform/FirstTransform.scala b/compiler/src/dotty/tools/dotc/transform/FirstTransform.scala
index a3459e890487..54483f74163a 100644
--- a/compiler/src/dotty/tools/dotc/transform/FirstTransform.scala
+++ b/compiler/src/dotty/tools/dotc/transform/FirstTransform.scala
@@ -138,7 +138,6 @@ class FirstTransform extends MiniPhase with InfoTransformer { thisPhase =>
   }
 
   override def transformOther(tree: Tree)(using Context): Tree = tree match {
-    case tree: Import if untpd.languageImport(tree.expr).isEmpty => EmptyTree
     case tree: Export => EmptyTree
     case tree: NamedArg => transformAllDeep(tree.arg)
     case tree => if (tree.isType) toTypeTree(tree) else tree
diff --git a/compiler/src/dotty/tools/dotc/typer/CrossVersionChecks.scala b/compiler/src/dotty/tools/dotc/typer/CrossVersionChecks.scala
index 41c0b6193c13..044dd7bb8528 100644
--- a/compiler/src/dotty/tools/dotc/typer/CrossVersionChecks.scala
+++ b/compiler/src/dotty/tools/dotc/typer/CrossVersionChecks.scala
@@ -33,7 +33,7 @@ class CrossVersionChecks extends MiniPhase:
     val xMigrationValue = ctx.settings.Xmigration.value
     if xMigrationValue != NoScalaVersion then
       checkMigration(sym, pos, xMigrationValue)
-
+  end checkUndesiredProperties
 
   /** If @deprecated is present, and the point of reference is not enclosed
    * in either a deprecated member or a scala bridge method, issue a warning.
@@ -176,6 +176,15 @@ class CrossVersionChecks extends MiniPhase:
     tree
   }
 
+  override def transformOther(tree: Tree)(using Context): Tree = tree match
+    case tree: Import =>
+      tree.foreachSubTree {
+        case t: RefTree => checkUndesiredProperties(t.symbol, t.srcPos)
+        case _ =>
+      }
+      tree
+    case _ => tree
+
 end CrossVersionChecks
 
 object CrossVersionChecks:
diff --git a/compiler/src/dotty/tools/repl/ReplDriver.scala b/compiler/src/dotty/tools/repl/ReplDriver.scala
index 184e1c0817fb..77be30bec25e 100644
--- a/compiler/src/dotty/tools/repl/ReplDriver.scala
+++ b/compiler/src/dotty/tools/repl/ReplDriver.scala
@@ -36,7 +36,7 @@ import org.jline.reader._
 
 import scala.annotation.tailrec
 import scala.collection.mutable
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 import scala.util.Using
 
 /** The state of the REPL contains necessary bindings instead of having to have
diff --git a/compiler/test/dotty/tools/TestSources.scala b/compiler/test/dotty/tools/TestSources.scala
index 76cf1d92e2bf..b4be973147e3 100644
--- a/compiler/test/dotty/tools/TestSources.scala
+++ b/compiler/test/dotty/tools/TestSources.scala
@@ -5,7 +5,7 @@ import scala.language.unsafeNulls
 import java.io.File
 import java.nio.file._
 
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 object TestSources {
 
diff --git a/compiler/test/dotty/tools/backend/jvm/AsmConverters.scala b/compiler/test/dotty/tools/backend/jvm/AsmConverters.scala
index 675e0c2014c3..a7900994d402 100644
--- a/compiler/test/dotty/tools/backend/jvm/AsmConverters.scala
+++ b/compiler/test/dotty/tools/backend/jvm/AsmConverters.scala
@@ -5,7 +5,7 @@ import scala.language.unsafeNulls
 import scala.tools.asm
 import asm._
 import asm.tree._
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 /** Makes using ASM from tests more convenient.
  *
diff --git a/compiler/test/dotty/tools/backend/jvm/AsmNode.scala b/compiler/test/dotty/tools/backend/jvm/AsmNode.scala
index 5918e1ecf198..caaf250eeafa 100644
--- a/compiler/test/dotty/tools/backend/jvm/AsmNode.scala
+++ b/compiler/test/dotty/tools/backend/jvm/AsmNode.scala
@@ -6,7 +6,7 @@ import java.lang.reflect.Modifier
 import scala.tools.asm
 import asm._
 import asm.tree._
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 sealed trait AsmNode[+T] {
   def node: T
diff --git a/compiler/test/dotty/tools/backend/jvm/DottyBytecodeTest.scala b/compiler/test/dotty/tools/backend/jvm/DottyBytecodeTest.scala
index ce887ec56ba9..6b7af09d4a2d 100644
--- a/compiler/test/dotty/tools/backend/jvm/DottyBytecodeTest.scala
+++ b/compiler/test/dotty/tools/backend/jvm/DottyBytecodeTest.scala
@@ -15,10 +15,9 @@ import dotty.tools.io.{VirtualDirectory => Directory}
 import scala.tools.asm
 import asm._
 import asm.tree._
-import scala.collection.JavaConverters._
 
 import io.{AbstractFile, JavaClassPath, VirtualDirectory}
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 import scala.tools.asm.{ClassWriter, ClassReader}
 import scala.tools.asm.tree._
 import java.io.{File => JFile, InputStream}
diff --git a/compiler/test/dotty/tools/backend/jvm/InlineBytecodeTests.scala b/compiler/test/dotty/tools/backend/jvm/InlineBytecodeTests.scala
index 1ad2340f6ed0..ea9009de1d9e 100644
--- a/compiler/test/dotty/tools/backend/jvm/InlineBytecodeTests.scala
+++ b/compiler/test/dotty/tools/backend/jvm/InlineBytecodeTests.scala
@@ -7,7 +7,7 @@ import org.junit.Test
 
 import scala.tools.asm.Opcodes._
 
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 class InlineBytecodeTests extends DottyBytecodeTest {
   import ASMConverters._
diff --git a/compiler/test/dotty/tools/dotc/CompilationTests.scala b/compiler/test/dotty/tools/dotc/CompilationTests.scala
index e64a06e684a4..5b18b6c81fe9 100644
--- a/compiler/test/dotty/tools/dotc/CompilationTests.scala
+++ b/compiler/test/dotty/tools/dotc/CompilationTests.scala
@@ -12,7 +12,7 @@ import org.junit.experimental.categories.Category
 import java.io.File
 import java.nio.file._
 import java.util.stream.{ Stream => JStream }
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 import scala.util.matching.Regex
 import scala.concurrent.duration._
 import TestSources.sources
diff --git a/compiler/test/dotty/tools/dotc/ConstantFoldingTests.scala b/compiler/test/dotty/tools/dotc/ConstantFoldingTests.scala
index fca82bf7a813..d40da245d7aa 100644
--- a/compiler/test/dotty/tools/dotc/ConstantFoldingTests.scala
+++ b/compiler/test/dotty/tools/dotc/ConstantFoldingTests.scala
@@ -9,7 +9,7 @@ import dotty.tools.dotc.config.CompilerCommand
 import dotty.tools.dotc.core.Contexts.FreshContext
 import scala.tools.asm.tree.MethodNode
 
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 class ConstantFoldingTests extends DottyBytecodeTest {
 
diff --git a/compiler/test/dotty/tools/dotc/TastyBootstrapTests.scala b/compiler/test/dotty/tools/dotc/TastyBootstrapTests.scala
index c95630144496..9e71b10b206d 100644
--- a/compiler/test/dotty/tools/dotc/TastyBootstrapTests.scala
+++ b/compiler/test/dotty/tools/dotc/TastyBootstrapTests.scala
@@ -12,7 +12,7 @@ import org.junit.experimental.categories.Category
 import java.io.File
 import java.nio.file._
 import java.util.stream.{ Stream => JStream }
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 import scala.util.matching.Regex
 import scala.concurrent.duration._
 import TestSources.sources
diff --git a/compiler/test/dotty/tools/dotc/classpath/MultiReleaseJarTest.scala b/compiler/test/dotty/tools/dotc/classpath/MultiReleaseJarTest.scala
index a878a25cf199..4375e14fddd8 100644
--- a/compiler/test/dotty/tools/dotc/classpath/MultiReleaseJarTest.scala
+++ b/compiler/test/dotty/tools/dotc/classpath/MultiReleaseJarTest.scala
@@ -12,7 +12,7 @@ import java.util.jar.Attributes.Name
 import org.junit.Assert._
 import org.junit.Test
 
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 import scala.util.Properties
 
 class MultiReleaseJarTest extends dotty.tools.backend.jvm.DottyBytecodeTest {
diff --git a/compiler/test/dotty/tools/dotc/transform/SpecializeFunctionsTests.scala b/compiler/test/dotty/tools/dotc/transform/SpecializeFunctionsTests.scala
index 5e095796551f..bf33dad915c4 100644
--- a/compiler/test/dotty/tools/dotc/transform/SpecializeFunctionsTests.scala
+++ b/compiler/test/dotty/tools/dotc/transform/SpecializeFunctionsTests.scala
@@ -10,7 +10,7 @@ import dotty.tools.backend.jvm.DottyBytecodeTest
 
 class SpecializeFunctionsTests extends DottyBytecodeTest {
 
-  import scala.collection.JavaConverters._
+  import scala.jdk.CollectionConverters._
 
   @Test def specializeParentIntToInt = {
     val source = """
diff --git a/compiler/test/dotty/tools/vulpix/SummaryReport.scala b/compiler/test/dotty/tools/vulpix/SummaryReport.scala
index 7043906e329d..e216ac1c5d4f 100644
--- a/compiler/test/dotty/tools/vulpix/SummaryReport.scala
+++ b/compiler/test/dotty/tools/vulpix/SummaryReport.scala
@@ -63,7 +63,7 @@ final class NoSummaryReport extends SummaryReporting {
  *  which outputs to a log file in `./testlogs/`
  */
 final class SummaryReport extends SummaryReporting {
-  import scala.collection.JavaConverters._
+  import scala.jdk.CollectionConverters._
 
   private val startingMessages = new java.util.concurrent.ConcurrentLinkedDeque[String]
   private val failedTests = new java.util.concurrent.ConcurrentLinkedDeque[String]
diff --git a/language-server/src/dotty/tools/languageserver/DottyLanguageServer.scala b/language-server/src/dotty/tools/languageserver/DottyLanguageServer.scala
index 5bc1e9f7dfa5..aeb1311b9ac7 100644
--- a/language-server/src/dotty/tools/languageserver/DottyLanguageServer.scala
+++ b/language-server/src/dotty/tools/languageserver/DottyLanguageServer.scala
@@ -12,7 +12,7 @@ import com.fasterxml.jackson.databind.ObjectMapper
 import org.eclipse.lsp4j
 
 import scala.collection._
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 import scala.util.control.NonFatal
 import scala.io.Codec
 
diff --git a/language-server/test/dotty/tools/languageserver/util/actions/CodeCompletion.scala b/language-server/test/dotty/tools/languageserver/util/actions/CodeCompletion.scala
index 90f7256c2293..250d88af4211 100644
--- a/language-server/test/dotty/tools/languageserver/util/actions/CodeCompletion.scala
+++ b/language-server/test/dotty/tools/languageserver/util/actions/CodeCompletion.scala
@@ -7,7 +7,7 @@ import dotty.tools.languageserver.util.server.TestFile
 import org.eclipse.lsp4j.{CompletionItem, CompletionItemKind}
 import org.junit.Assert.{assertEquals, assertFalse, assertTrue}
 
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 /**
  * An action requesting for code completion at `marker`, expecting `expected`.
diff --git a/language-server/test/dotty/tools/languageserver/util/actions/CodeDefinition.scala b/language-server/test/dotty/tools/languageserver/util/actions/CodeDefinition.scala
index 0ece0d9a5447..b20fa633d11e 100644
--- a/language-server/test/dotty/tools/languageserver/util/actions/CodeDefinition.scala
+++ b/language-server/test/dotty/tools/languageserver/util/actions/CodeDefinition.scala
@@ -3,7 +3,7 @@ package dotty.tools.languageserver.util.actions
 import dotty.tools.languageserver.util.{CodeRange, PositionContext}
 import dotty.tools.languageserver.util.embedded.CodeMarker
 
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 import org.junit.Assert.assertEquals
 
diff --git a/language-server/test/dotty/tools/languageserver/util/actions/CodeDocumentHighlight.scala b/language-server/test/dotty/tools/languageserver/util/actions/CodeDocumentHighlight.scala
index 58cb288716cc..b35a246178ff 100644
--- a/language-server/test/dotty/tools/languageserver/util/actions/CodeDocumentHighlight.scala
+++ b/language-server/test/dotty/tools/languageserver/util/actions/CodeDocumentHighlight.scala
@@ -5,7 +5,7 @@ import dotty.tools.languageserver.util.{CodeRange, PositionContext}
 import org.eclipse.lsp4j.DocumentHighlightKind
 import org.junit.Assert.assertEquals
 
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 /**
  * An action requesting for the ranges that should be highlighted, when a position within `range`
diff --git a/language-server/test/dotty/tools/languageserver/util/actions/CodeDocumentSymbol.scala b/language-server/test/dotty/tools/languageserver/util/actions/CodeDocumentSymbol.scala
index 79d401712476..2385ed067617 100644
--- a/language-server/test/dotty/tools/languageserver/util/actions/CodeDocumentSymbol.scala
+++ b/language-server/test/dotty/tools/languageserver/util/actions/CodeDocumentSymbol.scala
@@ -4,7 +4,7 @@ import dotty.tools.languageserver.util.embedded.CodeMarker
 import dotty.tools.languageserver.util.{PositionContext, SymInfo}
 import org.junit.Assert.assertEquals
 
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 /**
  * An action requesting for the symbols found in the document matching `marker`.
diff --git a/language-server/test/dotty/tools/languageserver/util/actions/CodeHover.scala b/language-server/test/dotty/tools/languageserver/util/actions/CodeHover.scala
index 0254e6470a5b..1bbfdd31d248 100644
--- a/language-server/test/dotty/tools/languageserver/util/actions/CodeHover.scala
+++ b/language-server/test/dotty/tools/languageserver/util/actions/CodeHover.scala
@@ -5,7 +5,7 @@ import dotty.tools.languageserver.util.{CodeRange, PositionContext}
 
 import org.junit.Assert.{assertEquals, assertNull, assertTrue}
 
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 /**
  * An action requesting for the info shown when `range` is hovered.
diff --git a/language-server/test/dotty/tools/languageserver/util/actions/CodeReferences.scala b/language-server/test/dotty/tools/languageserver/util/actions/CodeReferences.scala
index 8bd213e24dd7..d44e934a0dda 100644
--- a/language-server/test/dotty/tools/languageserver/util/actions/CodeReferences.scala
+++ b/language-server/test/dotty/tools/languageserver/util/actions/CodeReferences.scala
@@ -7,7 +7,7 @@ import org.junit.Assert.assertEquals
 
 import org.eclipse.lsp4j.Location
 
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 /**
  * An action requesting for all the references to the symbol in `range` within the workspace.
diff --git a/language-server/test/dotty/tools/languageserver/util/actions/CodeRename.scala b/language-server/test/dotty/tools/languageserver/util/actions/CodeRename.scala
index 78adb6dd1ac7..0b4df5452ec9 100644
--- a/language-server/test/dotty/tools/languageserver/util/actions/CodeRename.scala
+++ b/language-server/test/dotty/tools/languageserver/util/actions/CodeRename.scala
@@ -10,7 +10,7 @@ import org.eclipse.lsp4j.{MessageActionItem, ShowMessageRequestParams}
 
 import java.util.concurrent.CompletableFuture
 
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 /**
  * An action requesting for a rename of the symbol at `marker`.
diff --git a/language-server/test/dotty/tools/languageserver/util/actions/CodeSymbol.scala b/language-server/test/dotty/tools/languageserver/util/actions/CodeSymbol.scala
index 3fd5d59b15b4..421485ab434c 100644
--- a/language-server/test/dotty/tools/languageserver/util/actions/CodeSymbol.scala
+++ b/language-server/test/dotty/tools/languageserver/util/actions/CodeSymbol.scala
@@ -4,7 +4,7 @@ import dotty.tools.languageserver.util.{PositionContext, SymInfo}
 import org.eclipse.lsp4j.WorkspaceSymbolParams
 import org.junit.Assert.assertEquals
 
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 /**
  * An action requesting for all the symbols in the workspace matching `query`.
diff --git a/language-server/test/dotty/tools/languageserver/util/actions/Implementation.scala b/language-server/test/dotty/tools/languageserver/util/actions/Implementation.scala
index 4294382e6317..01da3ed0f41f 100644
--- a/language-server/test/dotty/tools/languageserver/util/actions/Implementation.scala
+++ b/language-server/test/dotty/tools/languageserver/util/actions/Implementation.scala
@@ -7,7 +7,7 @@ import org.eclipse.lsp4j.Location
 
 import org.junit.Assert.assertEquals
 
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 /**
  * An action requesting the implementations of the symbol inside `range`.
diff --git a/language-server/test/dotty/tools/languageserver/util/actions/SignatureHelp.scala b/language-server/test/dotty/tools/languageserver/util/actions/SignatureHelp.scala
index a3c10c887c44..4e1c0fcea77b 100644
--- a/language-server/test/dotty/tools/languageserver/util/actions/SignatureHelp.scala
+++ b/language-server/test/dotty/tools/languageserver/util/actions/SignatureHelp.scala
@@ -9,7 +9,7 @@ import dotty.tools.dotc.util.Signatures.Signature
 import org.eclipse.lsp4j.{MarkupContent, ParameterInformation, SignatureInformation}
 import org.junit.Assert.{assertEquals, assertFalse, assertTrue}
 
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 import SignatureHelp._
 
diff --git a/language-server/test/dotty/tools/languageserver/util/embedded/CodeMarker.scala b/language-server/test/dotty/tools/languageserver/util/embedded/CodeMarker.scala
index 392c40060556..416730dc0f4e 100644
--- a/language-server/test/dotty/tools/languageserver/util/embedded/CodeMarker.scala
+++ b/language-server/test/dotty/tools/languageserver/util/embedded/CodeMarker.scala
@@ -3,7 +3,7 @@ package dotty.tools.languageserver.util.embedded
 import dotty.tools.languageserver.util.server.TestFile
 import dotty.tools.languageserver.util.{CodeRange, PositionContext}
 
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 import org.eclipse.lsp4j._
 
diff --git a/sbt-test/source-dependencies/typeargref/A.scala b/sbt-test/source-dependencies/typeargref/A.scala
index ec3bd54f5c1d..f1f2c99be201 100644
--- a/sbt-test/source-dependencies/typeargref/A.scala
+++ b/sbt-test/source-dependencies/typeargref/A.scala
@@ -1,4 +1,4 @@
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 import java.util.{ Map => JMap }
 
 class A {
diff --git a/sbt-test/source-dependencies/typeargref/changes/A1.scala b/sbt-test/source-dependencies/typeargref/changes/A1.scala
index 9f85b963f2e7..257b795b33ed 100644
--- a/sbt-test/source-dependencies/typeargref/changes/A1.scala
+++ b/sbt-test/source-dependencies/typeargref/changes/A1.scala
@@ -1,4 +1,4 @@
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 import java.util.{ Map => JMap }
 
 class A {
diff --git a/scaladoc/src/dotty/tools/scaladoc/DocContext.scala b/scaladoc/src/dotty/tools/scaladoc/DocContext.scala
index 707cf4fbd1d5..7f208daff29a 100644
--- a/scaladoc/src/dotty/tools/scaladoc/DocContext.scala
+++ b/scaladoc/src/dotty/tools/scaladoc/DocContext.scala
@@ -5,7 +5,7 @@ import java.nio.file.Files
 import java.nio.file.Path
 import java.nio.file.Paths
 
-import collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 import dotty.tools.scaladoc.site.StaticSiteContext
 import dotty.tools.dotc.core.Contexts._
 import dotty.tools.dotc.util.SourceFile
diff --git a/scaladoc/src/dotty/tools/scaladoc/Main.scala b/scaladoc/src/dotty/tools/scaladoc/Main.scala
index c78af8bb52b7..da35e63561fd 100644
--- a/scaladoc/src/dotty/tools/scaladoc/Main.scala
+++ b/scaladoc/src/dotty/tools/scaladoc/Main.scala
@@ -3,7 +3,7 @@ package dotty.tools.scaladoc
 import java.util.ServiceLoader
 import java.io.File
 import java.util.jar._
-import collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 import collection.immutable.ArraySeq
 
 import java.nio.file.Files
diff --git a/scaladoc/src/dotty/tools/scaladoc/ScalaModuleProvider.scala b/scaladoc/src/dotty/tools/scaladoc/ScalaModuleProvider.scala
index eda96db893a3..3c38e07b3715 100644
--- a/scaladoc/src/dotty/tools/scaladoc/ScalaModuleProvider.scala
+++ b/scaladoc/src/dotty/tools/scaladoc/ScalaModuleProvider.scala
@@ -1,7 +1,7 @@
 package dotty.tools.scaladoc
 
 import dotty.tools.scaladoc.tasty.ScaladocTastyInspector
-import collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 import transformers._
 
 case class Module(rootPackage: Member, members: Map[DRI, Member])
diff --git a/scaladoc/src/dotty/tools/scaladoc/Scaladoc.scala b/scaladoc/src/dotty/tools/scaladoc/Scaladoc.scala
index 9d263441ace1..6e16684b82b5 100644
--- a/scaladoc/src/dotty/tools/scaladoc/Scaladoc.scala
+++ b/scaladoc/src/dotty/tools/scaladoc/Scaladoc.scala
@@ -4,7 +4,7 @@ import java.util.ServiceLoader
 import java.io.File
 import java.io.FileWriter
 import java.util.jar._
-import collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 import collection.immutable.ArraySeq
 
 import java.nio.file.{ Files, Paths }
diff --git a/scaladoc/src/dotty/tools/scaladoc/ScaladocCommand.scala b/scaladoc/src/dotty/tools/scaladoc/ScaladocCommand.scala
index de2d95dc457a..b91b8307208b 100644
--- a/scaladoc/src/dotty/tools/scaladoc/ScaladocCommand.scala
+++ b/scaladoc/src/dotty/tools/scaladoc/ScaladocCommand.scala
@@ -3,7 +3,7 @@ package dotty.tools.scaladoc
 import java.util.ServiceLoader
 import java.io.File
 import java.util.jar._
-import collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 import collection.immutable.ArraySeq
 
 import java.nio.file.Files
diff --git a/scaladoc/src/dotty/tools/scaladoc/ScaladocSettings.scala b/scaladoc/src/dotty/tools/scaladoc/ScaladocSettings.scala
index c1e7ead9950f..a2f4ff5f6c24 100644
--- a/scaladoc/src/dotty/tools/scaladoc/ScaladocSettings.scala
+++ b/scaladoc/src/dotty/tools/scaladoc/ScaladocSettings.scala
@@ -3,7 +3,7 @@ package dotty.tools.scaladoc
 import java.util.ServiceLoader
 import java.io.File
 import java.util.jar._
-import collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 import collection.immutable.ArraySeq
 
 import java.nio.file.Files
diff --git a/scaladoc/src/dotty/tools/scaladoc/compat.scala b/scaladoc/src/dotty/tools/scaladoc/compat.scala
index 35eab37fa1b5..fc660d97cb5d 100644
--- a/scaladoc/src/dotty/tools/scaladoc/compat.scala
+++ b/scaladoc/src/dotty/tools/scaladoc/compat.scala
@@ -6,7 +6,7 @@ import java.util.Collections
 import java.nio.file.Path
 import com.vladsch.flexmark.util.ast.{Node => MdNode}
 import dotty.tools.scaladoc.tasty.comments.wiki.WikiDocElement
-import collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 def JList[T](e: T*): JList[T] = e.asJava
 def JSet[T](e: T*): JSet[T] = e.toSet.asJava
diff --git a/scaladoc/src/dotty/tools/scaladoc/renderers/HtmlRenderer.scala b/scaladoc/src/dotty/tools/scaladoc/renderers/HtmlRenderer.scala
index 10e95046d220..2da0501cd606 100644
--- a/scaladoc/src/dotty/tools/scaladoc/renderers/HtmlRenderer.scala
+++ b/scaladoc/src/dotty/tools/scaladoc/renderers/HtmlRenderer.scala
@@ -2,7 +2,7 @@ package dotty.tools.scaladoc
 package renderers
 
 import util.HTML._
-import collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 import java.net.URI
 import java.net.URL
 import dotty.tools.scaladoc.site._
diff --git a/scaladoc/src/dotty/tools/scaladoc/renderers/Locations.scala b/scaladoc/src/dotty/tools/scaladoc/renderers/Locations.scala
index 12615671e538..deb676e812c8 100644
--- a/scaladoc/src/dotty/tools/scaladoc/renderers/Locations.scala
+++ b/scaladoc/src/dotty/tools/scaladoc/renderers/Locations.scala
@@ -2,7 +2,7 @@ package dotty.tools.scaladoc
 package renderers
 
 import util.HTML._
-import collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 import java.net.URI
 import java.net.URL
 import dotty.tools.scaladoc.site._
diff --git a/scaladoc/src/dotty/tools/scaladoc/renderers/MarkdownRenderer.scala b/scaladoc/src/dotty/tools/scaladoc/renderers/MarkdownRenderer.scala
index 5b074ad0a524..12d41ac86218 100644
--- a/scaladoc/src/dotty/tools/scaladoc/renderers/MarkdownRenderer.scala
+++ b/scaladoc/src/dotty/tools/scaladoc/renderers/MarkdownRenderer.scala
@@ -2,7 +2,7 @@ package dotty.tools.scaladoc
 package renderers
 
 import util.HTML._
-import collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 import java.net.URI
 import java.net.URL
 import dotty.tools.scaladoc.site._
diff --git a/scaladoc/src/dotty/tools/scaladoc/renderers/MemberRenderer.scala b/scaladoc/src/dotty/tools/scaladoc/renderers/MemberRenderer.scala
index 75d8ac4ee756..b8ec99399c21 100644
--- a/scaladoc/src/dotty/tools/scaladoc/renderers/MemberRenderer.scala
+++ b/scaladoc/src/dotty/tools/scaladoc/renderers/MemberRenderer.scala
@@ -3,7 +3,7 @@ package renderers
 
 import scala.collection.immutable.SortedMap
 import util.HTML._
-import collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 import dotty.tools.scaladoc.translators.FilterAttributes
 import dotty.tools.scaladoc.tasty.comments.markdown.DocFlexmarkRenderer
 import com.vladsch.flexmark.util.ast.{Node => MdNode}
@@ -30,7 +30,7 @@ class MemberRenderer(signatureRenderer: SignatureRenderer)(using DocContext) ext
 
   def inheritedFrom(m: Member) = m.inheritedFrom match
     case Some(InheritedFrom(name, dri, isSourceSuperclassHidden)) =>
-      val hiddenNameSuffix = if isSourceSuperclassHidden then " (hidden)" else "" 
+      val hiddenNameSuffix = if isSourceSuperclassHidden then " (hidden)" else ""
       tableRow("Inherited from:", signatureRenderer.renderLink(name + hiddenNameSuffix, dri))
     case _ => Nil
 
diff --git a/scaladoc/src/dotty/tools/scaladoc/renderers/Renderer.scala b/scaladoc/src/dotty/tools/scaladoc/renderers/Renderer.scala
index 4ce81450afbb..db22965b69d5 100644
--- a/scaladoc/src/dotty/tools/scaladoc/renderers/Renderer.scala
+++ b/scaladoc/src/dotty/tools/scaladoc/renderers/Renderer.scala
@@ -2,7 +2,7 @@ package dotty.tools.scaladoc
 package renderers
 
 import util.HTML._
-import collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 import collection.mutable.ListBuffer
 import java.net.URI
 import java.net.URL
diff --git a/scaladoc/src/dotty/tools/scaladoc/renderers/Resources.scala b/scaladoc/src/dotty/tools/scaladoc/renderers/Resources.scala
index e2965d5707ad..f9f73f01da9f 100644
--- a/scaladoc/src/dotty/tools/scaladoc/renderers/Resources.scala
+++ b/scaladoc/src/dotty/tools/scaladoc/renderers/Resources.scala
@@ -2,7 +2,7 @@ package dotty.tools.scaladoc
 package renderers
 
 import util.HTML._
-import collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 import java.net.URI
 import java.net.URL
 import dotty.tools.scaladoc.site._
diff --git a/scaladoc/src/dotty/tools/scaladoc/renderers/SignatureRenderer.scala b/scaladoc/src/dotty/tools/scaladoc/renderers/SignatureRenderer.scala
index 59ed3a697813..ed56dcc56c6a 100644
--- a/scaladoc/src/dotty/tools/scaladoc/renderers/SignatureRenderer.scala
+++ b/scaladoc/src/dotty/tools/scaladoc/renderers/SignatureRenderer.scala
@@ -2,7 +2,7 @@ package dotty.tools.scaladoc
 package renderers
 
 import util.HTML._
-import collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 import java.net.URI
 import java.net.URL
 import java.util.{List => JList, Set => JSet}
diff --git a/scaladoc/src/dotty/tools/scaladoc/renderers/SiteRenderer.scala b/scaladoc/src/dotty/tools/scaladoc/renderers/SiteRenderer.scala
index 5fa00c8f9374..15a8288aba2b 100644
--- a/scaladoc/src/dotty/tools/scaladoc/renderers/SiteRenderer.scala
+++ b/scaladoc/src/dotty/tools/scaladoc/renderers/SiteRenderer.scala
@@ -2,7 +2,7 @@ package dotty.tools.scaladoc
 package renderers
 
 import util.HTML._
-import collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 import java.net.URI
 import java.net.URL
 import dotty.tools.scaladoc.site._
diff --git a/scaladoc/src/dotty/tools/scaladoc/site/FlexmarkSectionWrapper.scala b/scaladoc/src/dotty/tools/scaladoc/site/FlexmarkSectionWrapper.scala
index 66903dd46dd4..12e93505ab59 100644
--- a/scaladoc/src/dotty/tools/scaladoc/site/FlexmarkSectionWrapper.scala
+++ b/scaladoc/src/dotty/tools/scaladoc/site/FlexmarkSectionWrapper.scala
@@ -5,7 +5,7 @@ import com.vladsch.flexmark.util.{ast => mdu, sequence}
 import com.vladsch.flexmark.{ast => mda}
 import com.vladsch.flexmark.formatter.Formatter
 import com.vladsch.flexmark.util.options.MutableDataSet
-import collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 import dotty.tools.scaladoc.tasty.comments.markdown.Section
 
diff --git a/scaladoc/src/dotty/tools/scaladoc/site/LoadedTemplate.scala b/scaladoc/src/dotty/tools/scaladoc/site/LoadedTemplate.scala
index fd5e50b2acba..b23e5647f6fb 100644
--- a/scaladoc/src/dotty/tools/scaladoc/site/LoadedTemplate.scala
+++ b/scaladoc/src/dotty/tools/scaladoc/site/LoadedTemplate.scala
@@ -6,7 +6,7 @@ import java.nio.file.Files
 import java.nio.file.Paths
 
 import org.jsoup.Jsoup
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 
 case class LazyEntry(getKey: String, value: () => String) extends JMapEntry[String, Object]:
diff --git a/scaladoc/src/dotty/tools/scaladoc/site/SidebarParser.scala b/scaladoc/src/dotty/tools/scaladoc/site/SidebarParser.scala
index 9d793c403b2d..1aefeaa21032 100644
--- a/scaladoc/src/dotty/tools/scaladoc/site/SidebarParser.scala
+++ b/scaladoc/src/dotty/tools/scaladoc/site/SidebarParser.scala
@@ -4,7 +4,7 @@ package site
 import com.fasterxml.jackson.dataformat.yaml.YAMLFactory;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.core.`type`.TypeReference;
-import collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 import java.util.Optional
 import scala.beans._
 
diff --git a/scaladoc/src/dotty/tools/scaladoc/site/StaticSiteContext.scala b/scaladoc/src/dotty/tools/scaladoc/site/StaticSiteContext.scala
index 51ee9e30e933..de3f511c8e67 100644
--- a/scaladoc/src/dotty/tools/scaladoc/site/StaticSiteContext.scala
+++ b/scaladoc/src/dotty/tools/scaladoc/site/StaticSiteContext.scala
@@ -8,7 +8,7 @@ import java.nio.file.Path
 import java.nio.file.Paths
 
 import scala.util.Try
-import collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 import scala.annotation.static
 
 class StaticSiteContext(
@@ -23,8 +23,8 @@ class StaticSiteContext(
   val docsPath = root.toPath.resolve("_docs")
   val blogPath = root.toPath.resolve("_blog")
 
-  def relativize(path: Path): Path = 
-    if args.apiSubdirectory then 
+  def relativize(path: Path): Path =
+    if args.apiSubdirectory then
       docsPath.relativize(path)
     else
       val relativised = docsPath.relativize(path)
diff --git a/scaladoc/src/dotty/tools/scaladoc/site/common.scala b/scaladoc/src/dotty/tools/scaladoc/site/common.scala
index 5c3c9eb8470e..6c4852961fec 100644
--- a/scaladoc/src/dotty/tools/scaladoc/site/common.scala
+++ b/scaladoc/src/dotty/tools/scaladoc/site/common.scala
@@ -17,7 +17,7 @@ import com.vladsch.flexmark.ext.wikilink.WikiLinkExtension
 import com.vladsch.flexmark.formatter.Formatter
 import com.vladsch.flexmark.html.HtmlRenderer
 
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 val docsRootDRI: DRI = DRI(location = "_docs/index", symbolUUID = staticFileSymbolUUID)
 val apiPageDRI: DRI = DRI(location = "api/index")
diff --git a/scaladoc/src/dotty/tools/scaladoc/site/templates.scala b/scaladoc/src/dotty/tools/scaladoc/site/templates.scala
index ba932e09653e..fe51bbe0614d 100644
--- a/scaladoc/src/dotty/tools/scaladoc/site/templates.scala
+++ b/scaladoc/src/dotty/tools/scaladoc/site/templates.scala
@@ -20,7 +20,7 @@ import liqp.parser.Flavor
 import liqp.TemplateContext
 import liqp.tags.Tag
 import liqp.nodes.LNode
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 import scala.io.Source
 import dotty.tools.scaladoc.snippets._
diff --git a/scaladoc/src/dotty/tools/scaladoc/snippets/FlexmarkSnippetProcessor.scala b/scaladoc/src/dotty/tools/scaladoc/snippets/FlexmarkSnippetProcessor.scala
index bc3bce308541..69e7c7764985 100644
--- a/scaladoc/src/dotty/tools/scaladoc/snippets/FlexmarkSnippetProcessor.scala
+++ b/scaladoc/src/dotty/tools/scaladoc/snippets/FlexmarkSnippetProcessor.scala
@@ -5,7 +5,7 @@ import com.vladsch.flexmark.util.{ast => mdu, sequence}
 import com.vladsch.flexmark.{ast => mda}
 import com.vladsch.flexmark.formatter.Formatter
 import com.vladsch.flexmark.util.options.MutableDataSet
-import collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 import dotty.tools.scaladoc.tasty.comments.markdown.ExtendedFencedCodeBlock
 import dotty.tools.scaladoc.tasty.comments.PreparsedComment
diff --git a/scaladoc/src/dotty/tools/scaladoc/tasty/BasicSupport.scala b/scaladoc/src/dotty/tools/scaladoc/tasty/BasicSupport.scala
index dc83ae77efbc..3ceecb5f4fcc 100644
--- a/scaladoc/src/dotty/tools/scaladoc/tasty/BasicSupport.scala
+++ b/scaladoc/src/dotty/tools/scaladoc/tasty/BasicSupport.scala
@@ -1,7 +1,7 @@
 package dotty.tools.scaladoc
 package tasty
 
-import collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 import dotty.tools.scaladoc._
 import scala.quoted._
 
diff --git a/scaladoc/src/dotty/tools/scaladoc/tasty/ClassLikeSupport.scala b/scaladoc/src/dotty/tools/scaladoc/tasty/ClassLikeSupport.scala
index 43dd224eaba0..0b435972997b 100644
--- a/scaladoc/src/dotty/tools/scaladoc/tasty/ClassLikeSupport.scala
+++ b/scaladoc/src/dotty/tools/scaladoc/tasty/ClassLikeSupport.scala
@@ -1,6 +1,6 @@
 package dotty.tools.scaladoc.tasty
 
-import collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 import dotty.tools.scaladoc._
 import dotty.tools.scaladoc.{Signature => DSignature}
 import dotty.tools.scaladoc.Inkuire
diff --git a/scaladoc/src/dotty/tools/scaladoc/tasty/InkuireSupport.scala b/scaladoc/src/dotty/tools/scaladoc/tasty/InkuireSupport.scala
index 1f3b353eb045..0cdb3535c3ff 100644
--- a/scaladoc/src/dotty/tools/scaladoc/tasty/InkuireSupport.scala
+++ b/scaladoc/src/dotty/tools/scaladoc/tasty/InkuireSupport.scala
@@ -1,6 +1,6 @@
 package dotty.tools.scaladoc.tasty
 
-import collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 import dotty.tools.scaladoc._
 import dotty.tools.scaladoc.{Signature => DSignature}
 import dotty.tools.scaladoc.Inkuire
diff --git a/scaladoc/src/dotty/tools/scaladoc/tasty/PackageSupport.scala b/scaladoc/src/dotty/tools/scaladoc/tasty/PackageSupport.scala
index 77ce9854620d..ee2490efbcc6 100644
--- a/scaladoc/src/dotty/tools/scaladoc/tasty/PackageSupport.scala
+++ b/scaladoc/src/dotty/tools/scaladoc/tasty/PackageSupport.scala
@@ -1,7 +1,7 @@
 package dotty.tools.scaladoc
 package tasty
 
-import collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 import SymOps._
 
diff --git a/scaladoc/src/dotty/tools/scaladoc/tasty/TypesSupport.scala b/scaladoc/src/dotty/tools/scaladoc/tasty/TypesSupport.scala
index 72bc62f95b7e..0cf2669407c8 100644
--- a/scaladoc/src/dotty/tools/scaladoc/tasty/TypesSupport.scala
+++ b/scaladoc/src/dotty/tools/scaladoc/tasty/TypesSupport.scala
@@ -1,7 +1,7 @@
 package dotty.tools.scaladoc
 package tasty
 
-import collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 import scala.quoted._
 
diff --git a/scaladoc/src/dotty/tools/scaladoc/tasty/comments/Comments.scala b/scaladoc/src/dotty/tools/scaladoc/tasty/comments/Comments.scala
index b62b1b7b3df8..89daf7152f22 100644
--- a/scaladoc/src/dotty/tools/scaladoc/tasty/comments/Comments.scala
+++ b/scaladoc/src/dotty/tools/scaladoc/tasty/comments/Comments.scala
@@ -14,7 +14,7 @@ import dotty.tools.scaladoc.tasty.comments.markdown.ExtendedFencedCodeBlock
 import dotty.tools.scaladoc.tasty.comments.wiki.Paragraph
 import dotty.tools.scaladoc.DocPart
 import dotty.tools.scaladoc.tasty.{ SymOpsWithLinkCache, SymOps }
-import collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 import dotty.tools.scaladoc.snippets._
 
 class Repr(val qctx: Quotes)(val sym: qctx.reflect.Symbol)
diff --git a/scaladoc/src/dotty/tools/scaladoc/tasty/comments/MarkdownParser.scala b/scaladoc/src/dotty/tools/scaladoc/tasty/comments/MarkdownParser.scala
index a3ab2d1a5eca..f5dd0ea88528 100644
--- a/scaladoc/src/dotty/tools/scaladoc/tasty/comments/MarkdownParser.scala
+++ b/scaladoc/src/dotty/tools/scaladoc/tasty/comments/MarkdownParser.scala
@@ -20,7 +20,7 @@ import com.vladsch.flexmark.ext.wikilink.WikiLinkExtension
 import com.vladsch.flexmark.util.options.{ DataHolder, MutableDataSet }
 import com.vladsch.flexmark.util.builder.Extension
 
-import collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 object MarkdownParser {
 
diff --git a/scaladoc/src/dotty/tools/scaladoc/tasty/comments/markdown/DocFlexmarkExtension.scala b/scaladoc/src/dotty/tools/scaladoc/tasty/comments/markdown/DocFlexmarkExtension.scala
index 1b9f10fb3185..ad5533d634ad 100644
--- a/scaladoc/src/dotty/tools/scaladoc/tasty/comments/markdown/DocFlexmarkExtension.scala
+++ b/scaladoc/src/dotty/tools/scaladoc/tasty/comments/markdown/DocFlexmarkExtension.scala
@@ -14,7 +14,7 @@ import com.vladsch.flexmark.util.sequence.BasedSequence
 import com.vladsch.flexmark._
 
 import dotty.tools.scaladoc.snippets._
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 class DocLinkNode(
   val target: DocLink,
diff --git a/scaladoc/test/dotty/tools/scaladoc/BaseHtmlTest.scala b/scaladoc/test/dotty/tools/scaladoc/BaseHtmlTest.scala
index 6de233aba1db..4b406170b033 100644
--- a/scaladoc/test/dotty/tools/scaladoc/BaseHtmlTest.scala
+++ b/scaladoc/test/dotty/tools/scaladoc/BaseHtmlTest.scala
@@ -44,7 +44,7 @@ class BaseHtmlTest:
     finally IO.delete(dest)
   end withGeneratedDoc
   class DocumentContext(d: Document, path: Path):
-    import collection.JavaConverters._
+    import scala.jdk.CollectionConverters._
 
     def niceMsg(msg: String) = s"$msg in $path (body):\n ${d.html()}:\n"
 
diff --git a/scaladoc/test/dotty/tools/scaladoc/PackageDocumentationTest.scala b/scaladoc/test/dotty/tools/scaladoc/PackageDocumentationTest.scala
index ca2ed505b09a..4d9458e563cb 100644
--- a/scaladoc/test/dotty/tools/scaladoc/PackageDocumentationTest.scala
+++ b/scaladoc/test/dotty/tools/scaladoc/PackageDocumentationTest.scala
@@ -3,7 +3,7 @@ package dotty.tools.scaladoc
 import org.junit.Assert._
 import com.vladsch.flexmark.util.{ast => mdu, sequence}
 import com.vladsch.flexmark.{ast => mda}
-import collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 
 class PackageDocumentationTest extends ScaladocTest("packageobjdocs"):
diff --git a/scaladoc/test/dotty/tools/scaladoc/snippets/SnippetsE2eTest.scala b/scaladoc/test/dotty/tools/scaladoc/snippets/SnippetsE2eTest.scala
index 11398855fc87..1f28c938033d 100644
--- a/scaladoc/test/dotty/tools/scaladoc/snippets/SnippetsE2eTest.scala
+++ b/scaladoc/test/dotty/tools/scaladoc/snippets/SnippetsE2eTest.scala
@@ -14,7 +14,7 @@ import com.vladsch.flexmark.util.{ast => mdu, sequence}
 import com.vladsch.flexmark.{ast => mda}
 import com.vladsch.flexmark.formatter.Formatter
 import com.vladsch.flexmark.util.options.MutableDataSet
-import collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 import dotty.tools.scaladoc.tasty.comments.markdown.ExtendedFencedCodeBlock
 
diff --git a/tests/disabled/partest/run/icode-reader-dead-code.scala b/tests/disabled/partest/run/icode-reader-dead-code.scala
index 00ba58829f71..157c2588ec60 100644
--- a/tests/disabled/partest/run/icode-reader-dead-code.scala
+++ b/tests/disabled/partest/run/icode-reader-dead-code.scala
@@ -4,7 +4,7 @@ import scala.tools.asm.{ClassWriter, Opcodes, ClassReader}
 import scala.tools.asm.tree.{InsnNode, ClassNode}
 import scala.tools.nsc.backend.jvm.AsmUtils
 import scala.tools.partest.DirectTest
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 /**
  * Test that the ICodeReader does not crash if the bytecode of a method has unreachable code.
diff --git a/tests/disabled/partest/run/t7852.scala b/tests/disabled/partest/run/t7852.scala
index 167906751042..ee04d1ba6267 100644
--- a/tests/disabled/partest/run/t7852.scala
+++ b/tests/disabled/partest/run/t7852.scala
@@ -2,7 +2,7 @@ import scala.tools.partest.BytecodeTest
 import scala.tools.asm
 import scala.tools.asm.util._
 import scala.tools.nsc.util.stringFromWriter
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 object Test extends BytecodeTest {
   val nullChecks = Set(asm.Opcodes.IFNONNULL, asm.Opcodes.IFNULL)
diff --git a/tests/disabled/partest/run/t8601-closure-elim.scala b/tests/disabled/partest/run/t8601-closure-elim.scala
index 2c5b03af772a..88ac58fc9e41 100644
--- a/tests/disabled/partest/run/t8601-closure-elim.scala
+++ b/tests/disabled/partest/run/t8601-closure-elim.scala
@@ -1,7 +1,7 @@
 import scala.tools.partest.BytecodeTest
 import scala.tools.asm
 import scala.tools.asm.util._
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 object Test extends BytecodeTest {
   val nullChecks = Set(asm.Opcodes.NEW)
diff --git a/tests/disabled/run/t5293-map.scala b/tests/disabled/run/t5293-map.scala
index ad1bbcfe30d3..41fcc03892c9 100644
--- a/tests/disabled/run/t5293-map.scala
+++ b/tests/disabled/run/t5293-map.scala
@@ -1,7 +1,7 @@
 
 
 
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 
 
diff --git a/tests/disabled/run/t5293.scala b/tests/disabled/run/t5293.scala
index c42c967b42e2..540885474801 100644
--- a/tests/disabled/run/t5293.scala
+++ b/tests/disabled/run/t5293.scala
@@ -1,7 +1,7 @@
 
 
 
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 
 
diff --git a/tests/idempotency/IdempotencyCheck.scala b/tests/idempotency/IdempotencyCheck.scala
index 598f68a8b347..ef7e3d09ed81 100644
--- a/tests/idempotency/IdempotencyCheck.scala
+++ b/tests/idempotency/IdempotencyCheck.scala
@@ -3,7 +3,7 @@ import java.io.File as JFile
 import java.nio.file.{ Files as JFiles, Path as JPath, Paths as JPaths }
 import java.util.stream.Stream as JStream
 
-import scala.collection.JavaConverters.*
+import scala.jdk.CollectionConverters.*
 
 object IdempotencyCheck {
   def checkIdempotency(dir1: String, dir2: String): Unit = {
diff --git a/tests/neg-custom-args/no-experimental/experimentalTerms.scala b/tests/neg-custom-args/no-experimental/experimentalTerms.scala
index 09b69d2da381..ada5e5b74d2c 100644
--- a/tests/neg-custom-args/no-experimental/experimentalTerms.scala
+++ b/tests/neg-custom-args/no-experimental/experimentalTerms.scala
@@ -14,7 +14,7 @@ def test1: Unit =
   f() // error: def f is marked @experimental and therefore ...
   x // error: value x is marked @experimental and therefore ...
   X.fx() // error: object X is marked @experimental and therefore ...
-  import X.fx
+  import X.fx // error: object X is marked @experimental and therefore ...
   fx() // error: object X is marked @experimental and therefore ...
 
 @experimental
diff --git a/tests/neg-strict/i15479.scala b/tests/neg-strict/i15479.scala
new file mode 100644
index 000000000000..3f8bdcba9a1f
--- /dev/null
+++ b/tests/neg-strict/i15479.scala
@@ -0,0 +1,16 @@
+package deptest {
+  @deprecated("Not used any more", since="7")
+  object DeprecatedThing {
+    val oldValue = 42
+  }
+}
+
+package depuser {
+  import deptest.DeprecatedThing.* // error
+
+  object DepUser {
+    def main(args: Array[String]): Unit = println {
+      oldValue
+    }
+  }
+}
\ No newline at end of file
diff --git a/tests/pos/Annotations.scala b/tests/pos/Annotations.scala
index 322cf2eafb06..87c3336ff3e8 100644
--- a/tests/pos/Annotations.scala
+++ b/tests/pos/Annotations.scala
@@ -1,6 +1,6 @@
 package foo.bar
 
-import jdk.jfr.Enabled
+class Enabled extends annotation.Annotation
 
 @Enabled
 @Deprecated
diff --git a/tests/pos/i2112.scala b/tests/pos/i2112.scala
index e9f43df2100a..cccd745cfe18 100644
--- a/tests/pos/i2112.scala
+++ b/tests/pos/i2112.scala
@@ -1,4 +1,4 @@
-import scala.collection.JavaConverters.*
+import scala.jdk.CollectionConverters.*
 
 object Test {
   def test(x: Any): Unit = {
diff --git a/tests/pos/javaConversions-2.10-ambiguity.scala b/tests/pos/javaConversions-2.10-ambiguity.scala
index b5aea14e1578..eab41743e40d 100644
--- a/tests/pos/javaConversions-2.10-ambiguity.scala
+++ b/tests/pos/javaConversions-2.10-ambiguity.scala
@@ -1,5 +1,5 @@
 import collection.{mutable, concurrent}
-import collection.JavaConverters.*
+import scala.jdk.CollectionConverters.*
 import java.util.concurrent.ConcurrentHashMap as CHM
 
 object Bar {
diff --git a/tests/run/t5974.scala b/tests/run/t5974.scala
index 1e12065d7cef..c7f4aa25a545 100644
--- a/tests/run/t5974.scala
+++ b/tests/run/t5974.scala
@@ -1,5 +1,5 @@
 object Test extends App {
-  import scala.collection.JavaConverters.*
+  import scala.jdk.CollectionConverters.*
 
   def ser(a: AnyRef) =
     (new java.io.ObjectOutputStream(new java.io.ByteArrayOutputStream())).writeObject(a)
diff --git a/tests/run/t6114.scala b/tests/run/t6114.scala
index 22d4df6149b6..140f6128e5c3 100644
--- a/tests/run/t6114.scala
+++ b/tests/run/t6114.scala
@@ -4,7 +4,7 @@ object Test extends App {
     list.add(1)
     list.add(2)
     list.add(3)
-    import scala.collection.JavaConverters.*
+    import scala.jdk.CollectionConverters.*
     val next = list.asScala ++ List(4,5,6)
     assert(next != list.asScala)
 
@@ -18,7 +18,7 @@ object Test extends App {
     set.add(1)
     set.add(2)
     set.add(3)
-    import scala.collection.JavaConverters.*
+    import scala.jdk.CollectionConverters.*
     val next = set.asScala ++ Set(4,5,6)
     assert(next != set.asScala)
 
@@ -32,7 +32,7 @@ object Test extends App {
     map.put(1,1)
     map.put(2,2)
     map.put(3,3)
-    import scala.collection.JavaConverters.*
+    import scala.jdk.CollectionConverters.*
     val next = map.asScala ++ Map(4->4,5->5,6->6)
     assert(next != map.asScala)
 
@@ -47,7 +47,7 @@ object Test extends App {
     list.add(1)
     list.add(2)
     list.add(3)
-    import scala.collection.JavaConverters.*
+    import scala.jdk.CollectionConverters.*
     val next = list.asScala ++ List(4,5,6)
     assert(next != list.asScala)