diff --git a/buildSrc/src/main/groovy/org/elasticsearch/gradle/BuildPlugin.groovy b/buildSrc/src/main/groovy/org/elasticsearch/gradle/BuildPlugin.groovy
index d59d25ddc55..4b709508662 100644
--- a/buildSrc/src/main/groovy/org/elasticsearch/gradle/BuildPlugin.groovy
+++ b/buildSrc/src/main/groovy/org/elasticsearch/gradle/BuildPlugin.groovy
@@ -561,8 +561,6 @@ class BuildPlugin implements Plugin<Project> {
              */
             List html4Projects = [
                 ':server',
-                ':libs:elasticsearch-core',
-                ':test:framework',
                 ':x-pack:plugin:core',
             ]
             if (false == html4Projects.contains(project.path)) {
diff --git a/libs/elasticsearch-core/src/main/java/org/elasticsearch/common/Booleans.java b/libs/elasticsearch-core/src/main/java/org/elasticsearch/common/Booleans.java
index 7447f0111f7..86877857965 100644
--- a/libs/elasticsearch-core/src/main/java/org/elasticsearch/common/Booleans.java
+++ b/libs/elasticsearch-core/src/main/java/org/elasticsearch/common/Booleans.java
@@ -107,7 +107,7 @@ public final class Booleans {
     }
 
     /**
-     * Returns <code>false</code> if text is in <tt>false</tt>, <tt>0</tt>, <tt>off</tt>, <tt>no</tt>; else, true
+     * Returns {@code false} if text is in "false", "0", "off", "no"; else, {@code true}.
      *
      * @deprecated Only kept to provide automatic upgrades for pre 6.0 indices. Use {@link #parseBoolean(String, Boolean)} instead.
      */
@@ -119,9 +119,7 @@ public final class Booleans {
         return parseBooleanLenient(value, false);
     }
     /**
-     * Returns <code>true</code> iff the value is neither of the following:
-     *   <tt>false</tt>, <tt>0</tt>, <tt>off</tt>, <tt>no</tt>
-     *   otherwise <code>false</code>
+     * Returns {@code false} if text is in "false", "0", "off", "no"; else, {@code true}.
      *
      * @deprecated Only kept to provide automatic upgrades for pre 6.0 indices. Use {@link #parseBoolean(String, boolean)} instead.
      */
@@ -134,21 +132,21 @@ public final class Booleans {
     }
 
     /**
-     * @return <code>true</code> iff the value is <tt>false</tt>, otherwise <code>false</code>.
+     * @return {@code true} iff the value is "false", otherwise {@code false}.
      */
     public static boolean isFalse(String value) {
         return "false".equals(value);
     }
 
     /**
-     * @return <code>true</code> iff the value is <tt>true</tt>, otherwise <code>false</code>
+     * @return {@code true} iff the value is "true", otherwise {@code false}.
      */
     public static boolean isTrue(String value) {
         return "true".equals(value);
     }
 
     /**
-     * Returns <code>false</code> if text is in <tt>false</tt>, <tt>0</tt>, <tt>off</tt>, <tt>no</tt>; else, true
+     * Returns {@code false} if text is in "false", "0", "off", "no"; else, {@code true}.
      *
      * @deprecated Only kept to provide automatic upgrades for pre 6.0 indices. Use {@link #parseBoolean(char[], int, int, boolean)} instead
      */
diff --git a/libs/elasticsearch-core/src/main/java/org/elasticsearch/core/internal/io/IOUtils.java b/libs/elasticsearch-core/src/main/java/org/elasticsearch/core/internal/io/IOUtils.java
index 4108992fb1f..67663516167 100644
--- a/libs/elasticsearch-core/src/main/java/org/elasticsearch/core/internal/io/IOUtils.java
+++ b/libs/elasticsearch-core/src/main/java/org/elasticsearch/core/internal/io/IOUtils.java
@@ -37,11 +37,11 @@ import java.util.Map;
 public final class IOUtils {
 
     private IOUtils() {
-
+        // Static utils methods
     }
 
     /**
-     * Closes all given <tt>Closeable</tt>s. Some of the <tt>Closeable</tt>s may be null; they are
+     * Closes all given {@link Closeable}s. Some of the {@linkplain Closeable}s may be null; they are
      * ignored. After everything is closed, the method either throws the first exception it hit
      * while closing with other exceptions added as suppressed, or completes normally if there were
      * no exceptions.
@@ -53,7 +53,7 @@ public final class IOUtils {
     }
 
     /**
-     * Closes all given <tt>Closeable</tt>s. Some of the <tt>Closeable</tt>s may be null; they are
+     * Closes all given {@link Closeable}s. Some of the {@linkplain Closeable}s may be null; they are
      * ignored. After everything is closed, the method adds any exceptions as suppressed to the
      * original exception, or throws the first exception it hit if {@code Exception} is null. If
      * no exceptions are encountered and the passed in exception is null, it completes normally.
@@ -65,7 +65,7 @@ public final class IOUtils {
     }
 
     /**
-     * Closes all given <tt>Closeable</tt>s. Some of the <tt>Closeable</tt>s may be null; they are
+     * Closes all given {@link Closeable}s. Some of the {@linkplain Closeable}s may be null; they are
      * ignored. After everything is closed, the method either throws the first exception it hit
      * while closing with other exceptions added as suppressed, or completes normally if there were
      * no exceptions.
diff --git a/test/framework/src/main/java/org/elasticsearch/test/ESIntegTestCase.java b/test/framework/src/main/java/org/elasticsearch/test/ESIntegTestCase.java
index 2d027e8bfec..a7fd6768064 100644
--- a/test/framework/src/main/java/org/elasticsearch/test/ESIntegTestCase.java
+++ b/test/framework/src/main/java/org/elasticsearch/test/ESIntegTestCase.java
@@ -1352,7 +1352,7 @@ public abstract class ESIntegTestCase extends ESTestCase {
      * segment or if only one document is in a segment etc. This method prevents issues like this by randomizing the index
      * layout.
      *
-     * @param forceRefresh if <tt>true</tt> all involved indices are refreshed once the documents are indexed. Additionally if <tt>true</tt>
+     * @param forceRefresh if {@code true} all involved indices are refreshed once the documents are indexed. Additionally if {@code true}
      *                     some empty dummy documents are may be randomly inserted into the document list and deleted once all documents are indexed.
      *                     This is useful to produce deleted documents on the server side.
      * @param builders     the documents to index.
@@ -1369,8 +1369,8 @@ public abstract class ESIntegTestCase extends ESTestCase {
      * segment or if only one document is in a segment etc. This method prevents issues like this by randomizing the index
      * layout.
      *
-     * @param forceRefresh   if <tt>true</tt> all involved indices are refreshed once the documents are indexed.
-     * @param dummyDocuments if <tt>true</tt> some empty dummy documents may be randomly inserted into the document list and deleted once
+     * @param forceRefresh   if {@code true} all involved indices are refreshed once the documents are indexed.
+     * @param dummyDocuments if {@code true} some empty dummy documents may be randomly inserted into the document list and deleted once
      *                       all documents are indexed. This is useful to produce deleted documents on the server side.
      * @param builders       the documents to index.
      */
@@ -1385,10 +1385,10 @@ public abstract class ESIntegTestCase extends ESTestCase {
      * segment or if only one document is in a segment etc. This method prevents issues like this by randomizing the index
      * layout.
      *
-     * @param forceRefresh   if <tt>true</tt> all involved indices are refreshed once the documents are indexed.
-     * @param dummyDocuments if <tt>true</tt> some empty dummy documents may be randomly inserted into the document list and deleted once
+     * @param forceRefresh   if {@code true} all involved indices are refreshed once the documents are indexed.
+     * @param dummyDocuments if {@code true} some empty dummy documents may be randomly inserted into the document list and deleted once
      *                       all documents are indexed. This is useful to produce deleted documents on the server side.
-     * @param maybeFlush     if <tt>true</tt> this method may randomly execute full flushes after index operations.
+     * @param maybeFlush     if {@code true} this method may randomly execute full flushes after index operations.
      * @param builders       the documents to index.
      */
     public void indexRandom(boolean forceRefresh, boolean dummyDocuments, boolean maybeFlush, List<IndexRequestBuilder> builders) throws InterruptedException, ExecutionException {
@@ -1554,27 +1554,27 @@ public abstract class ESIntegTestCase extends ESTestCase {
         Scope scope() default Scope.SUITE;
 
         /**
-         * Returns the number of nodes in the cluster. Default is <tt>-1</tt> which means
+         * Returns the number of nodes in the cluster. Default is {@code -1} which means
          * a random number of nodes is used, where the minimum and maximum number of nodes
          * are either the specified ones or the default ones if not specified.
          */
         int numDataNodes() default -1;
 
         /**
-         * Returns the minimum number of data nodes in the cluster. Default is <tt>-1</tt>.
+         * Returns the minimum number of data nodes in the cluster. Default is {@code -1}.
          * Ignored when {@link ClusterScope#numDataNodes()} is set.
          */
         int minNumDataNodes() default -1;
 
         /**
-         * Returns the maximum number of data nodes in the cluster.  Default is <tt>-1</tt>.
+         * Returns the maximum number of data nodes in the cluster.  Default is {@code -1}.
          * Ignored when {@link ClusterScope#numDataNodes()} is set.
          */
         int maxNumDataNodes() default -1;
 
         /**
-         * Indicates whether the cluster can have dedicated master nodes. If <tt>false</tt> means data nodes will serve as master nodes
-         * and there will be no dedicated master (and data) nodes. Default is <tt>true</tt> which means
+         * Indicates whether the cluster can have dedicated master nodes. If {@code false} means data nodes will serve as master nodes
+         * and there will be no dedicated master (and data) nodes. Default is {@code false} which means
          * dedicated master nodes will be randomly used.
          */
         boolean supportsDedicatedMasters() default true;
@@ -1703,7 +1703,7 @@ public abstract class ESIntegTestCase extends ESTestCase {
     }
 
     /**
-     * This method is used to obtain settings for the <tt>Nth</tt> node in the cluster.
+     * This method is used to obtain settings for the {@code N}th node in the cluster.
      * Nodes in this cluster are associated with an ordinal number such that nodes can
      * be started with specific configurations. This method might be called multiple
      * times with the same ordinal and is expected to return the same value for each invocation.
@@ -1878,7 +1878,7 @@ public abstract class ESIntegTestCase extends ESTestCase {
 
     /**
      * Iff this returns true mock transport implementations are used for the test runs. Otherwise not mock transport impls are used.
-     * The default is <tt>true</tt>
+     * The default is {@code true}.
      */
     protected boolean addMockTransportService() {
         return true;
@@ -1886,7 +1886,7 @@ public abstract class ESIntegTestCase extends ESTestCase {
 
     /**
      * Iff this returns true test zen discovery implementations is used for the test runs.
-     * The default is <tt>true</tt>
+     * The default is {@code true}.
      */
     protected boolean addTestZenDiscovery() {
         return true;
@@ -1957,7 +1957,7 @@ public abstract class ESIntegTestCase extends ESTestCase {
     /**
      * Returns the transport client ratio from the class level annotation or via
      * {@link System#getProperty(String)} if available. If both are not available this will
-     * return a random ratio in the interval <tt>[0..1]</tt>
+     * return a random ratio in the interval {@code [0..1]}.
      */
     protected double getPerTestTransportClientRatio() {
         final ClusterScope annotation = getAnnotation(this.getClass(), ClusterScope.class);
diff --git a/test/framework/src/main/java/org/elasticsearch/test/InternalTestCluster.java b/test/framework/src/main/java/org/elasticsearch/test/InternalTestCluster.java
index 12acd21903e..5099fc0540d 100644
--- a/test/framework/src/main/java/org/elasticsearch/test/InternalTestCluster.java
+++ b/test/framework/src/main/java/org/elasticsearch/test/InternalTestCluster.java
@@ -1978,7 +1978,7 @@ public final class InternalTestCluster extends TestCluster {
         }
 
         /**
-         * Executed for each node before the <tt>n+1</tt> node is restarted. The given client is
+         * Executed for each node before the {@code n + 1} node is restarted. The given client is
          * an active client to the node that will be restarted next.
          */
         public void doAfterNodes(int n, Client client) throws Exception {
diff --git a/test/framework/src/main/java/org/elasticsearch/test/XContentTestUtils.java b/test/framework/src/main/java/org/elasticsearch/test/XContentTestUtils.java
index 15c650173bf..724a99f2c94 100644
--- a/test/framework/src/main/java/org/elasticsearch/test/XContentTestUtils.java
+++ b/test/framework/src/main/java/org/elasticsearch/test/XContentTestUtils.java
@@ -145,7 +145,7 @@ public final class XContentTestUtils {
      * If the xContent output contains objects that should be skipped of such treatment, an optional filtering
      * {@link Predicate} can be supplied that checks xContent paths that should be excluded from this treatment.
      *
-     * This predicate should check the xContent path that we want to insert to and return <tt>true</tt> if the
+     * This predicate should check the xContent path that we want to insert to and return {@code true} if the
      * path should be excluded. Paths are string concatenating field names and array indices, so e.g. in:
      *
      * <pre>
diff --git a/test/framework/src/main/java/org/elasticsearch/test/engine/MockEngineSupport.java b/test/framework/src/main/java/org/elasticsearch/test/engine/MockEngineSupport.java
index bf0b7376b81..fc2a85b35a9 100644
--- a/test/framework/src/main/java/org/elasticsearch/test/engine/MockEngineSupport.java
+++ b/test/framework/src/main/java/org/elasticsearch/test/engine/MockEngineSupport.java
@@ -19,14 +19,13 @@
 package org.elasticsearch.test.engine;
 
 import org.apache.logging.log4j.Logger;
+import org.apache.lucene.index.AssertingDirectoryReader;
 import org.apache.lucene.index.DirectoryReader;
 import org.apache.lucene.index.FilterDirectoryReader;
 import org.apache.lucene.index.IndexReader;
 import org.apache.lucene.search.AssertingIndexSearcher;
-import org.apache.lucene.search.IndexSearcher;
 import org.apache.lucene.search.QueryCache;
 import org.apache.lucene.search.QueryCachingPolicy;
-import org.apache.lucene.search.ReferenceManager;
 import org.apache.lucene.util.LuceneTestCase;
 import org.elasticsearch.ElasticsearchException;
 import org.elasticsearch.common.logging.Loggers;
@@ -38,6 +37,7 @@ import org.elasticsearch.index.engine.EngineConfig;
 import org.elasticsearch.index.engine.EngineException;
 import org.elasticsearch.index.shard.ShardId;
 import org.elasticsearch.test.ESIntegTestCase;
+import org.elasticsearch.test.engine.MockInternalEngine;
 
 import java.io.Closeable;
 import java.io.IOException;
@@ -47,14 +47,15 @@ import java.util.Random;
 import java.util.concurrent.atomic.AtomicBoolean;
 
 /**
- * Support class to build MockEngines like {@link org.elasticsearch.test.engine.MockInternalEngine}
+ * Support class to build MockEngines like {@link MockInternalEngine}
  * since they need to subclass the actual engine
  */
 public final class MockEngineSupport {
 
     /**
-     * Allows tests to wrap an index reader randomly with a given ratio. This is disabled by default ie. <tt>0.0d</tt> since reader wrapping is insanely
-     * slow if {@link org.apache.lucene.index.AssertingDirectoryReader} is used.
+     * Allows tests to wrap an index reader randomly with a given ratio. This
+     * is disabled by default ie. {@code 0.0d} since reader wrapping is insanely
+     * slow if {@link AssertingDirectoryReader} is used.
      */
     public static final Setting<Double> WRAP_READER_RATIO =
         Setting.doubleSetting("index.engine.mock.random.wrap_reader_ratio", 0.0d, 0.0d, Property.IndexScope);
diff --git a/test/framework/src/main/java/org/elasticsearch/test/transport/MockTransportService.java b/test/framework/src/main/java/org/elasticsearch/test/transport/MockTransportService.java
index 1c31533c933..6654444066d 100644
--- a/test/framework/src/main/java/org/elasticsearch/test/transport/MockTransportService.java
+++ b/test/framework/src/main/java/org/elasticsearch/test/transport/MockTransportService.java
@@ -474,7 +474,7 @@ public final class MockTransportService extends TransportService {
     /**
      * Adds a new delegate transport that is used for communication with the given transport service.
      *
-     * @return <tt>true</tt> iff no other delegate was registered for any of the addresses bound by transport service.
+     * @return {@code true} iff no other delegate was registered for any of the addresses bound by transport service.
      */
     public boolean addDelegate(TransportService transportService, DelegateTransport transport) {
         boolean noRegistered = true;
@@ -487,7 +487,7 @@ public final class MockTransportService extends TransportService {
     /**
      * Adds a new delegate transport that is used for communication with the given transport address.
      *
-     * @return <tt>true</tt> iff no other delegate was registered for this address before.
+     * @return {@code true} iff no other delegate was registered for this address before.
      */
     public boolean addDelegate(TransportAddress transportAddress, DelegateTransport transport) {
         return transport().transports.put(transportAddress, transport) == null;