Merge "Implement filtering and lazy loading of checks"
diff --git a/java/com/google/gerrit/extensions/common/ActionInfo.java b/java/com/google/gerrit/extensions/common/ActionInfo.java
index 6ab80b2..8039949 100644
--- a/java/com/google/gerrit/extensions/common/ActionInfo.java
+++ b/java/com/google/gerrit/extensions/common/ActionInfo.java
@@ -15,6 +15,7 @@
 package com.google.gerrit.extensions.common;
 
 import com.google.gerrit.extensions.webui.UiAction;
+import java.util.Objects;
 
 /**
  * Representation of an action in the REST API.
@@ -55,4 +56,21 @@
     title = d.getTitle();
     enabled = d.isEnabled() ? true : null;
   }
+
+  @Override
+  public boolean equals(Object o) {
+    if (o instanceof ActionInfo) {
+      ActionInfo actionInfo = (ActionInfo) o;
+      return Objects.equals(method, actionInfo.method)
+          && Objects.equals(label, actionInfo.label)
+          && Objects.equals(title, actionInfo.title)
+          && Objects.equals(enabled, actionInfo.enabled);
+    }
+    return false;
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(method, label, title, enabled);
+  }
 }
diff --git a/java/com/google/gerrit/extensions/common/ApprovalInfo.java b/java/com/google/gerrit/extensions/common/ApprovalInfo.java
index f95ddff..bf72e83 100644
--- a/java/com/google/gerrit/extensions/common/ApprovalInfo.java
+++ b/java/com/google/gerrit/extensions/common/ApprovalInfo.java
@@ -16,6 +16,7 @@
 
 import com.google.gerrit.common.Nullable;
 import java.sql.Timestamp;
+import java.util.Objects;
 
 /**
  * Representation of an approval in the REST API.
@@ -71,4 +72,23 @@
     this.date = date;
     this.tag = tag;
   }
+
+  @Override
+  public boolean equals(Object o) {
+    if (o instanceof ApprovalInfo) {
+      ApprovalInfo approvalInfo = (ApprovalInfo) o;
+      return super.equals(o)
+          && Objects.equals(tag, approvalInfo.tag)
+          && Objects.equals(value, approvalInfo.value)
+          && Objects.equals(date, approvalInfo.date)
+          && Objects.equals(postSubmit, approvalInfo.postSubmit)
+          && Objects.equals(permittedVotingRange, approvalInfo.permittedVotingRange);
+    }
+    return false;
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(super.hashCode(), tag, value, date, postSubmit, permittedVotingRange);
+  }
 }
diff --git a/java/com/google/gerrit/extensions/common/AttentionSetInfo.java b/java/com/google/gerrit/extensions/common/AttentionSetInfo.java
index f29d32b..490d394 100644
--- a/java/com/google/gerrit/extensions/common/AttentionSetInfo.java
+++ b/java/com/google/gerrit/extensions/common/AttentionSetInfo.java
@@ -15,6 +15,7 @@
 package com.google.gerrit.extensions.common;
 
 import java.sql.Timestamp;
+import java.util.Objects;
 
 /**
  * Represents a single user included in the attention set. Used in the API. See {@link
@@ -36,4 +37,20 @@
     this.lastUpdate = lastUpdate;
     this.reason = reason;
   }
+
+  @Override
+  public boolean equals(Object o) {
+    if (o instanceof AttentionSetInfo) {
+      AttentionSetInfo attentionSetInfo = (AttentionSetInfo) o;
+      return Objects.equals(account, attentionSetInfo.account)
+          && Objects.equals(lastUpdate, attentionSetInfo.lastUpdate)
+          && Objects.equals(reason, attentionSetInfo.reason);
+    }
+    return false;
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(account, lastUpdate, reason);
+  }
 }
diff --git a/java/com/google/gerrit/extensions/common/AvatarInfo.java b/java/com/google/gerrit/extensions/common/AvatarInfo.java
index 75665a8..b620ac2 100644
--- a/java/com/google/gerrit/extensions/common/AvatarInfo.java
+++ b/java/com/google/gerrit/extensions/common/AvatarInfo.java
@@ -14,6 +14,8 @@
 
 package com.google.gerrit.extensions.common;
 
+import java.util.Objects;
+
 /**
  * Representation of an avatar in the REST API.
  *
@@ -38,4 +40,20 @@
 
   /** The width of the avatar image in pixels. */
   public Integer width;
+
+  @Override
+  public boolean equals(Object o) {
+    if (o instanceof AvatarInfo) {
+      AvatarInfo avatarInfo = (AvatarInfo) o;
+      return Objects.equals(url, avatarInfo.url)
+          && Objects.equals(height, avatarInfo.height)
+          && Objects.equals(width, avatarInfo.width);
+    }
+    return false;
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(url, height, width);
+  }
 }
diff --git a/java/com/google/gerrit/extensions/common/FetchInfo.java b/java/com/google/gerrit/extensions/common/FetchInfo.java
index eda84b1..472dba2 100644
--- a/java/com/google/gerrit/extensions/common/FetchInfo.java
+++ b/java/com/google/gerrit/extensions/common/FetchInfo.java
@@ -15,6 +15,7 @@
 package com.google.gerrit.extensions.common;
 
 import java.util.Map;
+import java.util.Objects;
 
 public class FetchInfo {
   public String url;
@@ -25,4 +26,20 @@
     this.url = url;
     this.ref = ref;
   }
+
+  @Override
+  public boolean equals(Object o) {
+    if (o instanceof FetchInfo) {
+      FetchInfo fetchInfo = (FetchInfo) o;
+      return Objects.equals(url, fetchInfo.url)
+          && Objects.equals(ref, fetchInfo.ref)
+          && Objects.equals(commands, fetchInfo.commands);
+    }
+    return false;
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(url, ref, commands);
+  }
 }
diff --git a/java/com/google/gerrit/extensions/common/GpgKeyInfo.java b/java/com/google/gerrit/extensions/common/GpgKeyInfo.java
index 7a5c15b..d656f22 100644
--- a/java/com/google/gerrit/extensions/common/GpgKeyInfo.java
+++ b/java/com/google/gerrit/extensions/common/GpgKeyInfo.java
@@ -15,6 +15,7 @@
 package com.google.gerrit.extensions.common;
 
 import java.util.List;
+import java.util.Objects;
 
 public class GpgKeyInfo {
   /**
@@ -43,4 +44,22 @@
 
   public Status status;
   public List<String> problems;
+
+  @Override
+  public boolean equals(Object o) {
+    if (o instanceof GpgKeyInfo) {
+      GpgKeyInfo gpgKeyInfo = (GpgKeyInfo) o;
+      return Objects.equals(id, gpgKeyInfo.id)
+          && Objects.equals(fingerprint, gpgKeyInfo.fingerprint)
+          && Objects.equals(userIds, gpgKeyInfo.userIds)
+          && Objects.equals(status, gpgKeyInfo.status)
+          && Objects.equals(problems, gpgKeyInfo.problems);
+    }
+    return false;
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(id, fingerprint, userIds, status, problems);
+  }
 }
diff --git a/java/com/google/gerrit/extensions/common/LabelInfo.java b/java/com/google/gerrit/extensions/common/LabelInfo.java
index 76dd93d..44bcdaf 100644
--- a/java/com/google/gerrit/extensions/common/LabelInfo.java
+++ b/java/com/google/gerrit/extensions/common/LabelInfo.java
@@ -16,6 +16,7 @@
 
 import java.util.List;
 import java.util.Map;
+import java.util.Objects;
 
 public class LabelInfo {
   public AccountInfo approved;
@@ -30,4 +31,37 @@
   public Short defaultValue;
   public Boolean optional;
   public Boolean blocking;
+
+  @Override
+  public boolean equals(Object o) {
+    if (o instanceof LabelInfo) {
+      LabelInfo labelInfo = (LabelInfo) o;
+      return Objects.equals(approved, labelInfo.approved)
+          && Objects.equals(rejected, labelInfo.rejected)
+          && Objects.equals(recommended, labelInfo.recommended)
+          && Objects.equals(disliked, labelInfo.disliked)
+          && Objects.equals(all, labelInfo.all)
+          && Objects.equals(values, labelInfo.values)
+          && Objects.equals(value, labelInfo.value)
+          && Objects.equals(defaultValue, labelInfo.defaultValue)
+          && Objects.equals(optional, labelInfo.optional)
+          && Objects.equals(blocking, labelInfo.blocking);
+    }
+    return false;
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(
+        approved,
+        rejected,
+        recommended,
+        disliked,
+        all,
+        values,
+        value,
+        defaultValue,
+        optional,
+        blocking);
+  }
 }
diff --git a/java/com/google/gerrit/extensions/common/PluginDefinedInfo.java b/java/com/google/gerrit/extensions/common/PluginDefinedInfo.java
index 69bfa2c..e2b1c36 100644
--- a/java/com/google/gerrit/extensions/common/PluginDefinedInfo.java
+++ b/java/com/google/gerrit/extensions/common/PluginDefinedInfo.java
@@ -14,7 +14,24 @@
 
 package com.google.gerrit.extensions.common;
 
+import java.util.Objects;
+
 public class PluginDefinedInfo {
   public String name;
   public String message;
+
+  @Override
+  public boolean equals(Object o) {
+    if (o instanceof PluginDefinedInfo) {
+      PluginDefinedInfo pluginDefinedInfo = (PluginDefinedInfo) o;
+      return Objects.equals(name, pluginDefinedInfo.name)
+          && Objects.equals(message, pluginDefinedInfo.message);
+    }
+    return false;
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(name, message);
+  }
 }
diff --git a/java/com/google/gerrit/extensions/common/PushCertificateInfo.java b/java/com/google/gerrit/extensions/common/PushCertificateInfo.java
index 9eed808..199dbd1 100644
--- a/java/com/google/gerrit/extensions/common/PushCertificateInfo.java
+++ b/java/com/google/gerrit/extensions/common/PushCertificateInfo.java
@@ -14,7 +14,24 @@
 
 package com.google.gerrit.extensions.common;
 
+import java.util.Objects;
+
 public class PushCertificateInfo {
   public String certificate;
   public GpgKeyInfo key;
+
+  @Override
+  public boolean equals(Object o) {
+    if (o instanceof PushCertificateInfo) {
+      PushCertificateInfo pushCertificateInfo = (PushCertificateInfo) o;
+      return Objects.equals(certificate, pushCertificateInfo.certificate)
+          && Objects.equals(key, pushCertificateInfo.key);
+    }
+    return false;
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(certificate, key);
+  }
 }
diff --git a/java/com/google/gerrit/extensions/common/ReviewerUpdateInfo.java b/java/com/google/gerrit/extensions/common/ReviewerUpdateInfo.java
index eccdc64..37e1ceb 100644
--- a/java/com/google/gerrit/extensions/common/ReviewerUpdateInfo.java
+++ b/java/com/google/gerrit/extensions/common/ReviewerUpdateInfo.java
@@ -16,10 +16,28 @@
 
 import com.google.gerrit.extensions.client.ReviewerState;
 import java.sql.Timestamp;
+import java.util.Objects;
 
 public class ReviewerUpdateInfo {
   public Timestamp updated;
   public AccountInfo updatedBy;
   public AccountInfo reviewer;
   public ReviewerState state;
+
+  @Override
+  public boolean equals(Object o) {
+    if (o instanceof ReviewerUpdateInfo) {
+      ReviewerUpdateInfo reviewerUpdateInfo = (ReviewerUpdateInfo) o;
+      return Objects.equals(updated, reviewerUpdateInfo.updated)
+          && Objects.equals(updatedBy, reviewerUpdateInfo.updatedBy)
+          && Objects.equals(reviewer, reviewerUpdateInfo.reviewer)
+          && Objects.equals(state, reviewerUpdateInfo.state);
+    }
+    return false;
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(updated, updatedBy, reviewer, state);
+  }
 }
diff --git a/java/com/google/gerrit/extensions/common/RevisionInfo.java b/java/com/google/gerrit/extensions/common/RevisionInfo.java
index f262901..ea61f31 100644
--- a/java/com/google/gerrit/extensions/common/RevisionInfo.java
+++ b/java/com/google/gerrit/extensions/common/RevisionInfo.java
@@ -17,6 +17,7 @@
 import com.google.gerrit.extensions.client.ChangeKind;
 import java.sql.Timestamp;
 import java.util.Map;
+import java.util.Objects;
 
 public class RevisionInfo {
   // ActionJson#copy(List, RevisionInfo) must be adapted if new fields are added that are not
@@ -34,4 +35,43 @@
   public String commitWithFooters;
   public PushCertificateInfo pushCertificate;
   public String description;
+
+  @Override
+  public boolean equals(Object o) {
+    if (o instanceof RevisionInfo) {
+      RevisionInfo revisionInfo = (RevisionInfo) o;
+      return isCurrent == revisionInfo.isCurrent
+          && Objects.equals(kind, revisionInfo.kind)
+          && _number == revisionInfo._number
+          && Objects.equals(created, revisionInfo.created)
+          && Objects.equals(uploader, revisionInfo.uploader)
+          && Objects.equals(ref, revisionInfo.ref)
+          && Objects.equals(fetch, revisionInfo.fetch)
+          && Objects.equals(commit, revisionInfo.commit)
+          && Objects.equals(files, revisionInfo.files)
+          && Objects.equals(actions, revisionInfo.actions)
+          && Objects.equals(commitWithFooters, revisionInfo.commitWithFooters)
+          && Objects.equals(pushCertificate, revisionInfo.pushCertificate)
+          && Objects.equals(description, revisionInfo.description);
+    }
+    return false;
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(
+        isCurrent,
+        kind,
+        _number,
+        created,
+        uploader,
+        ref,
+        fetch,
+        commit,
+        files,
+        actions,
+        commitWithFooters,
+        pushCertificate,
+        description);
+  }
 }
diff --git a/java/com/google/gerrit/extensions/common/TrackingIdInfo.java b/java/com/google/gerrit/extensions/common/TrackingIdInfo.java
index 0c5ed68..d9b8e22 100644
--- a/java/com/google/gerrit/extensions/common/TrackingIdInfo.java
+++ b/java/com/google/gerrit/extensions/common/TrackingIdInfo.java
@@ -14,6 +14,8 @@
 
 package com.google.gerrit.extensions.common;
 
+import java.util.Objects;
+
 public class TrackingIdInfo {
   public String system;
   public String id;
@@ -22,4 +24,18 @@
     this.system = system;
     this.id = id;
   }
+
+  @Override
+  public boolean equals(Object o) {
+    if (o instanceof TrackingIdInfo) {
+      TrackingIdInfo trackingIdInfo = (TrackingIdInfo) o;
+      return Objects.equals(system, trackingIdInfo.system) && Objects.equals(id, trackingIdInfo.id);
+    }
+    return false;
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(system, id);
+  }
 }
diff --git a/java/com/google/gerrit/extensions/common/VotingRangeInfo.java b/java/com/google/gerrit/extensions/common/VotingRangeInfo.java
index 5c35a49..2f7e9e4 100644
--- a/java/com/google/gerrit/extensions/common/VotingRangeInfo.java
+++ b/java/com/google/gerrit/extensions/common/VotingRangeInfo.java
@@ -14,6 +14,8 @@
 
 package com.google.gerrit.extensions.common;
 
+import java.util.Objects;
+
 public class VotingRangeInfo {
   public int min;
   public int max;
@@ -22,4 +24,18 @@
     this.min = min;
     this.max = max;
   }
+
+  @Override
+  public boolean equals(Object o) {
+    if (o instanceof VotingRangeInfo) {
+      VotingRangeInfo votingRangeInfo = (VotingRangeInfo) o;
+      return min == votingRangeInfo.min && max == votingRangeInfo.max;
+    }
+    return false;
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(min, max);
+  }
 }
diff --git a/polygerrit-ui/app/elements/change/gr-change-requirements/gr-change-requirements_html.ts b/polygerrit-ui/app/elements/change/gr-change-requirements/gr-change-requirements_html.ts
index f172ccc..e02b337 100644
--- a/polygerrit-ui/app/elements/change/gr-change-requirements/gr-change-requirements_html.ts
+++ b/polygerrit-ui/app/elements/change/gr-change-requirements/gr-change-requirements_html.ts
@@ -99,6 +99,9 @@
       padding-left: 0;
     }
   </style>
+  <template is="dom-if" if="[[_isNewChangeSummaryUiEnabled]]">
+    <h3 class="metadata-title">Submit requirements</h3>
+  </template>
   <template is="dom-repeat" items="[[_requirements]]">
     <gr-endpoint-decorator
       class="submit-requirement-endpoints"
@@ -126,9 +129,6 @@
       </div>
     </gr-endpoint-decorator>
   </template>
-  <template is="dom-if" if="[[_isNewChangeSummaryUiEnabled]]">
-    <h3 class="metadata-title">Submit requirements</h3>
-  </template>
   <template is="dom-repeat" items="[[_requiredLabels]]">
     <section>
       <div class="title">
diff --git a/polygerrit-ui/app/elements/change/gr-change-view/gr-change-view.ts b/polygerrit-ui/app/elements/change/gr-change-view/gr-change-view.ts
index 304939c..3d7646f 100644
--- a/polygerrit-ui/app/elements/change/gr-change-view/gr-change-view.ts
+++ b/polygerrit-ui/app/elements/change/gr-change-view/gr-change-view.ts
@@ -2313,6 +2313,7 @@
                 return response;
               });
           }
+          // TODO: use returned Promise
           this.getRelatedChangesListExperimental()?.reload(
             relatedChangesPromise
           );
diff --git a/polygerrit-ui/app/elements/change/gr-related-changes-list-experimental/gr-related-changes-list-experimental.ts b/polygerrit-ui/app/elements/change/gr-related-changes-list-experimental/gr-related-changes-list-experimental.ts
index 11f0fd3..e921979 100644
--- a/polygerrit-ui/app/elements/change/gr-related-changes-list-experimental/gr-related-changes-list-experimental.ts
+++ b/polygerrit-ui/app/elements/change/gr-related-changes-list-experimental/gr-related-changes-list-experimental.ts
@@ -16,9 +16,12 @@
  */
 import {html, nothing} from 'lit-html';
 import './gr-related-change';
+import '../../plugins/gr-endpoint-decorator/gr-endpoint-decorator';
+import '../../plugins/gr-endpoint-param/gr-endpoint-param';
+import '../../plugins/gr-endpoint-slot/gr-endpoint-slot';
 import {classMap} from 'lit-html/directives/class-map';
 import {GrLitElement} from '../../lit/gr-lit-element';
-import {customElement, property, css} from 'lit-element';
+import {customElement, property, css, internalProperty} from 'lit-element';
 import {sharedStyles} from '../../../styles/shared-styles';
 import {
   SubmittedTogetherInfo,
@@ -32,7 +35,11 @@
 import {ParsedChangeInfo} from '../../../types/types';
 import {GerritNav} from '../../core/gr-navigation/gr-navigation';
 import {pluralize} from '../../../utils/string-util';
-import {getRevisionKey, isChangeInfo} from '../../../utils/change-util';
+import {
+  changeIsOpen,
+  getRevisionKey,
+  isChangeInfo,
+} from '../../../utils/change-util';
 
 /** What is the maximum number of shown changes in collapsed list? */
 const MAX_CHANGES_WHEN_COLLAPSED = 3;
@@ -46,13 +53,25 @@
   patchNum?: PatchSetNum;
 
   @property()
-  _submittedTogether?: SubmittedTogetherInfo = {
+  mergeable?: boolean;
+
+  @internalProperty()
+  submittedTogether?: SubmittedTogetherInfo = {
     changes: [],
     non_visible_changes: 0,
   };
 
-  @property()
-  _relatedResponse?: RelatedChangesInfo = {changes: []};
+  @internalProperty()
+  relatedChanges: RelatedChangeAndCommitInfo[] = [];
+
+  @internalProperty()
+  conflictingChanges: ChangeInfo[] = [];
+
+  @internalProperty()
+  cherryPickChanges: ChangeInfo[] = [];
+
+  @internalProperty()
+  sameTopicChanges: ChangeInfo[] = [];
 
   private readonly restApiService = appContext.restApiService;
 
@@ -62,6 +81,7 @@
       css`
         .note {
           color: var(--error-text-color);
+          margin-left: 1.2em;
         }
         section {
           margin-bottom: var(--spacing-m);
@@ -71,27 +91,26 @@
   }
 
   render() {
-    const relatedChanges = this._relatedResponse?.changes ?? [];
     let showWhenCollapsedPredicate = this.showWhenCollapsedPredicateFactory(
-      relatedChanges.length,
-      relatedChanges.findIndex(relatedChange =>
+      this.relatedChanges.length,
+      this.relatedChanges.findIndex(relatedChange =>
         this._changesEqual(relatedChange, this.change)
       )
     );
     const connectedRevisions = this._computeConnectedRevisions(
       this.change,
       this.patchNum,
-      relatedChanges
+      this.relatedChanges
     );
     const relatedChangeSection = html` <section
       class="relatedChanges"
-      ?hidden=${!relatedChanges.length}
+      ?hidden=${!this.relatedChanges.length}
     >
       <gr-related-collapse
         title="Relation chain"
-        .length=${relatedChanges.length}
+        .length=${this.relatedChanges.length}
       >
-        ${relatedChanges.map(
+        ${this.relatedChanges.map(
           (change, index) =>
             html`<gr-related-change
               class="${classMap({
@@ -114,9 +133,9 @@
       </gr-related-collapse>
     </section>`;
 
-    const submittedTogetherChanges = this._submittedTogether?.changes ?? [];
+    const submittedTogetherChanges = this.submittedTogether?.changes ?? [];
     const countNonVisibleChanges =
-      this._submittedTogether?.non_visible_changes ?? 0;
+      this.submittedTogether?.non_visible_changes ?? 0;
     showWhenCollapsedPredicate = this.showWhenCollapsedPredicateFactory(
       submittedTogetherChanges.length,
       submittedTogetherChanges.findIndex(relatedChange =>
@@ -126,7 +145,7 @@
     const submittedTogetherSection = html`<section
       id="submittedTogether"
       ?hidden=${!submittedTogetherChanges?.length &&
-      !this._submittedTogether?.non_visible_changes}
+      !this.submittedTogether?.non_visible_changes}
     >
       <gr-related-collapse
         title="Submitted together"
@@ -155,11 +174,106 @@
       </div>
     </section>`;
 
-    return html`${relatedChangeSection}${submittedTogetherSection}`;
+    showWhenCollapsedPredicate = this.showWhenCollapsedPredicateFactory(
+      this.sameTopicChanges.length,
+      -1
+    );
+    const sameTopicSection = html`<section
+      id="sameTopic"
+      ?hidden=${!this.sameTopicChanges?.length}
+    >
+      <gr-related-collapse
+        title="Same topic"
+        .length=${this.sameTopicChanges.length}
+      >
+        ${this.sameTopicChanges.map(
+          (change, index) =>
+            html`<gr-related-change
+              class="${classMap({
+                ['show-when-collapsed']: showWhenCollapsedPredicate(index),
+              })}"
+              .change="${change}"
+              .href="${GerritNav.getUrlForChangeById(
+                change._number,
+                change.project
+              )}"
+              >${change.project}: ${change.branch}:
+              ${change.subject}</gr-related-change
+            >`
+        )}
+      </gr-related-collapse>
+    </section>`;
+
+    showWhenCollapsedPredicate = this.showWhenCollapsedPredicateFactory(
+      this.conflictingChanges.length,
+      -1
+    );
+    const mergeConflictsSection = html`<section
+      id="mergeConflicts"
+      ?hidden=${!this.conflictingChanges?.length}
+    >
+      <gr-related-collapse
+        title="Merge conflicts"
+        .length=${this.conflictingChanges.length}
+      >
+        ${this.conflictingChanges.map(
+          (change, index) =>
+            html`<gr-related-change
+              class="${classMap({
+                ['show-when-collapsed']: showWhenCollapsedPredicate(index),
+              })}"
+              .change="${change}"
+              .href="${GerritNav.getUrlForChangeById(
+                change._number,
+                change.project
+              )}"
+              >${change.subject}</gr-related-change
+            >`
+        )}
+      </gr-related-collapse>
+    </section>`;
+
+    showWhenCollapsedPredicate = this.showWhenCollapsedPredicateFactory(
+      this.cherryPickChanges.length,
+      -1
+    );
+    const cherryPicksSection = html`<section
+      id="cherryPicks"
+      ?hidden=${!this.cherryPickChanges?.length}
+    >
+      <gr-related-collapse
+        title="Cherry picks"
+        .length=${this.cherryPickChanges.length}
+      >
+        ${this.cherryPickChanges.map(
+          (change, index) =>
+            html`<gr-related-change
+              class="${classMap({
+                ['show-when-collapsed']: showWhenCollapsedPredicate(index),
+              })}"
+              .change="${change}"
+              .href="${GerritNav.getUrlForChangeById(
+                change._number,
+                change.project
+              )}"
+              >${change.branch}: ${change.subject}</gr-related-change
+            >`
+        )}
+      </gr-related-collapse>
+    </section>`;
+
+    return html`<gr-endpoint-decorator name="related-changes-section">
+      <gr-endpoint-param name="change" value="[[change]]"></gr-endpoint-param>
+      <gr-endpoint-slot name="top"></gr-endpoint-slot>
+      ${relatedChangeSection} ${submittedTogetherSection} ${sameTopicSection}
+      ${mergeConflictsSection} ${cherryPicksSection}
+      <gr-endpoint-slot name="bottom"></gr-endpoint-slot>
+    </gr-endpoint-decorator>`;
   }
 
   showWhenCollapsedPredicateFactory(length: number, highlightIndex: number) {
     return (index: number) => {
+      if (highlightIndex === -1) return index < MAX_CHANGES_WHEN_COLLAPSED;
       if (highlightIndex === 0) return index <= MAX_CHANGES_WHEN_COLLAPSED - 1;
       if (highlightIndex === length - 1)
         return index >= length - MAX_CHANGES_WHEN_COLLAPSED;
@@ -171,21 +285,60 @@
   }
 
   reload(getRelatedChanges?: Promise<RelatedChangesInfo | undefined>) {
-    if (!this.change) return Promise.reject(new Error('change missing'));
+    const change = this.change;
+    if (!change) return Promise.reject(new Error('change missing'));
+    if (!this.patchNum) return Promise.reject(new Error('patchNum missing'));
+    if (!getRelatedChanges) {
+      getRelatedChanges = this.restApiService.getRelatedChanges(
+        change._number,
+        this.patchNum
+      );
+    }
     const promises: Array<Promise<void>> = [
+      getRelatedChanges.then(response => {
+        if (!response) {
+          throw new Error('getRelatedChanges returned undefined response');
+        }
+        this.relatedChanges = response?.changes ?? [];
+      }),
       this.restApiService
-        .getChangesSubmittedTogether(this.change._number)
+        .getChangesSubmittedTogether(change._number)
         .then(response => {
-          this._submittedTogether = response;
+          this.submittedTogether = response;
+        }),
+      this.restApiService
+        .getChangeCherryPicks(change.project, change.change_id, change._number)
+        .then(response => {
+          this.cherryPickChanges = response || [];
         }),
     ];
-    if (getRelatedChanges) {
+
+    // Get conflicts if change is open and is mergeable.
+    // Mergeable is output of restApiServict.getMergeable from gr-change-view
+    if (changeIsOpen(change) && this.mergeable) {
       promises.push(
-        getRelatedChanges.then(response => {
-          if (!response) {
-            throw new Error('getRelatedChanges returned undefined response');
+        this.restApiService
+          .getChangeConflicts(change._number)
+          .then(response => {
+            this.conflictingChanges = response ?? [];
+          })
+      );
+    }
+    if (change.topic) {
+      const changeTopic = change.topic;
+      promises.push(
+        this.restApiService.getConfig().then(config => {
+          if (config && !config.change.submit_whole_topic) {
+            return this.restApiService
+              .getChangesWithSameTopic(changeTopic, change._number)
+              .then(response => {
+                if (changeTopic === this.change?.topic) {
+                  this.sameTopicChanges = response ?? [];
+                }
+              });
           }
-          this._relatedResponse = response;
+          this.sameTopicChanges = [];
+          return Promise.resolve();
         })
       );
     }
diff --git a/polygerrit-ui/app/elements/change/gr-related-changes-list/gr-related-changes-list_html.ts b/polygerrit-ui/app/elements/change/gr-related-changes-list/gr-related-changes-list_html.ts
index 8cb0638..9941fa9 100644
--- a/polygerrit-ui/app/elements/change/gr-related-changes-list/gr-related-changes-list_html.ts
+++ b/polygerrit-ui/app/elements/change/gr-related-changes-list/gr-related-changes-list_html.ts
@@ -193,6 +193,7 @@
               href$="[[_computeChangeURL(change._number, change.project)]]"
               class$="[[_computeLinkClass(change)]]"
               title$="[[change.subject]]"
+              on-click="_reportClick"
             >
               [[change.subject]]
             </a>
diff --git a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-annotation-actions-js-api.ts b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-annotation-actions-js-api.ts
index 95252cf..a3d038d 100644
--- a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-annotation-actions-js-api.ts
+++ b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-annotation-actions-js-api.ts
@@ -120,12 +120,8 @@
    * Don't forget to also call disposeLayer().
    */
   createLayer(path: string, changeNum: number) {
-    if (!this.annotationCallback) return undefined;
-    const annotationLayer = new AnnotationLayer(
-      path,
-      changeNum,
-      this.annotationCallback
-    );
+    const callbackFn = this.annotationCallback || (() => {});
+    const annotationLayer = new AnnotationLayer(path, changeNum, callbackFn);
     this.annotationLayers.push(annotationLayer);
     return annotationLayer;
   }