Extensions suddenly have org.codehaus.plexus:plexus-utils:jar:1.1 on their classpath

<project xmlns="http://maven.apache.org/POM/4.0.0"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0
  http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>test</groupId>
<artifactId>test</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>maven-archetype</packaging>
<name>test</name>

<build>
  <extensions> 
    <extension>
      <groupId>org.apache.maven.archetype</groupId>
      <artifactId>archetype-packaging</artifactId>
      <version>3.1.2</version>
    </extension>
  </extensions>

  <pluginManagement>
    <plugins>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-archetype-plugin</artifactId>
        <version>3.1.2</version>
      </plugin>
    </plugins>
  </pluginManagement>
</build>
</project>

[DEBUG] Dependency collection stats: {ConflictMarker.analyzeTime=952800, ConflictMarker.markTime=586900, ConflictMarker.nodeCount=1, ConflictIdSorter.graphTime=549200, ConflictIdSorter.topsortTime=586700, ConflictIdSorter.conflictIdCount=1, ConflictIdSorter.conflictIdCycleCount=0, ConflictResolver.totalTime=3313100, ConflictResolver.conflictItemCount=1, DefaultDependencyCollector.collectTime=66890900, DefaultDependencyCollector.transformTime=8523500}
[DEBUG] org.apache.maven.archetype:archetype-packaging:jar:3.1.2:
[DEBUG]    org.codehaus.plexus:plexus-utils:jar:1.1:runtime