diff --git a/src/main/java/testingbot/TestingBotBuildObject.java b/src/main/java/testingbot/TestingBotBuildObject.java
index b7cb564..100c02f 100644
--- a/src/main/java/testingbot/TestingBotBuildObject.java
+++ b/src/main/java/testingbot/TestingBotBuildObject.java
@@ -11,7 +11,6 @@ public class TestingBotBuildObject implements Serializable {
     private String testName;
     private final boolean isPassed;
     private String authHash;
-    private TestingbotTest test;
     private String environmentName;
 
     public TestingBotBuildObject(String sessionId, String className, String testName, boolean isPassed, String authHash, TestingbotTest test) {
@@ -20,7 +19,8 @@ public TestingBotBuildObject(String sessionId, String className, String testName
       this.testName = testName;
       this.isPassed = isPassed;
       this.authHash = authHash;
-      this.test = test;
+      // TestingbotTest is only used here to derive the environment label; it is not stored (it is not
+      // marshalable under the JEP-200 class filter, and nothing reads it afterwards).
       this.environmentName = test == null ? "" : test.getBrowser() + " | " + test.getOs();
     }
 
@@ -81,20 +81,6 @@ public boolean getIsPassed() {
         return isPassed;
     }
 
-    /**
-     * @return the test
-     */
-    public TestingbotTest getTest() {
-        return test;
-    }
-
-    /**
-     * @param test the test to set
-     */
-    public void setTest(TestingbotTest test) {
-        this.test = test;
-    }
-
     /**
      * @return the authHash
      */
diff --git a/src/main/java/testingbot/TestingBotTestEmbed.java b/src/main/java/testingbot/TestingBotTestEmbed.java
index 10dc935..05a6a5a 100644
--- a/src/main/java/testingbot/TestingBotTestEmbed.java
+++ b/src/main/java/testingbot/TestingBotTestEmbed.java
@@ -2,21 +2,16 @@
 
 import hudson.model.Run;
 import jenkins.model.RunAction2;
-import org.kohsuke.stapler.Stapler;
-import org.kohsuke.stapler.StaplerRequest;
-import org.kohsuke.stapler.StaplerResponse;
+import org.kohsuke.stapler.StaplerRequest2;
+import org.kohsuke.stapler.StaplerResponse2;
 
-import javax.servlet.ServletException;
+import jakarta.servlet.ServletException;
 import java.io.IOException;
 import java.util.List;
-import java.util.logging.Level;
-import java.util.logging.Logger;
 
 public class TestingBotTestEmbed implements RunAction2 {
-    private static final Logger logger = Logger.getLogger(TestingBotTestEmbed.class.getName());
     private transient Run run;
     private List<TestingBotBuildObject> ids;
-    private TestingBotBuildObject tbo;
 
     public TestingBotTestEmbed(List<TestingBotBuildObject> ids) {
         this.ids = ids;
@@ -48,32 +43,28 @@ public void onLoad(Run<?, ?> run) {
     }
 
     /**
-     *
      * @param req Standard Request Object
      * @param rsp Standard Response Object
-     * @throws IOException Unable to load show.jelly template
+     * @throws IOException Unable to load the view template
      */
     @SuppressWarnings("unused") // used by stapler
-    public void doIndex(StaplerRequest req, StaplerResponse rsp)
+    public void doIndex(StaplerRequest2 req, StaplerResponse2 rsp)
             throws IOException {
         String sessionId = req.getParameter("sessionId");
-        for (TestingBotBuildObject tbo : this.ids) {
-            if (tbo.getSessionId().equals(sessionId)) {
-                this.tbo = tbo;
+        TestingBotBuildObject selected = null;
+        for (TestingBotBuildObject candidate : this.ids) {
+            if (candidate.getSessionId().equals(sessionId)) {
+                selected = candidate;
+                break;
             }
         }
-        if (this.tbo != null) {
-            try {
-                req.getView(this, "show.jelly").forward(req, rsp);
-            } catch (ServletException e) {
-                throw new IOException(e);
-            }
-        } else {
-            try {
-                req.getView(this, "index.jelly").forward(req, rsp);
-            } catch (ServletException e) {
-                throw new IOException(e);
-            }
+        // Pass the selection through the request (this action is shared across concurrent requests,
+        // so a per-instance field would let requests overwrite each other's selected session).
+        req.setAttribute("tbo", selected);
+        try {
+            req.getView(this, selected != null ? "show.jelly" : "index.jelly").forward(req, rsp);
+        } catch (ServletException e) {
+            throw new IOException(e);
         }
     }
 
@@ -81,10 +72,6 @@ public Run getRun() {
         return run;
     }
 
-    public TestingBotBuildObject getTbo() {
-        return tbo;
-    }
-
     public List<TestingBotBuildObject> getSessionIds() {
         return ids;
     }
diff --git a/src/main/resources/testingbot/TestingBotTestEmbed/show.jelly b/src/main/resources/testingbot/TestingBotTestEmbed/show.jelly
index 9daf2a1..1f23d1e 100644
--- a/src/main/resources/testingbot/TestingBotTestEmbed/show.jelly
+++ b/src/main/resources/testingbot/TestingBotTestEmbed/show.jelly
@@ -5,11 +5,12 @@
             <st:include page="sidepanel.jelly" it="${it.run}" optional="true" />
         </l:side-panel>
         <l:main-panel>
-            <h1>${it.tbo.testName}</h1>
-            <a href="https://testingbot.com/tests/${it.tbo.sessionId}?auth=${it.tbo.authHash}&amp;ref=jenkins" target="_blank">View on TestingBot</a>
+            <j:set var="tbo" value="${request.getAttribute('tbo')}"/>
+            <h1>${tbo.testName}</h1>
+            <a href="https://testingbot.com/tests/${tbo.sessionId}?auth=${tbo.authHash}&amp;ref=jenkins" target="_blank">View on TestingBot</a>
             <l:ajax>
                 <div>
-                    <iframe src="https://testingbot.com/mini/?id=${it.tbo.sessionId}&amp;auth=${it.tbo.authHash}&amp;ref=jenkins" style="width: 100%; min-height: 100vh; border: none"></iframe>
+                    <iframe src="https://testingbot.com/mini/?id=${tbo.sessionId}&amp;auth=${tbo.authHash}&amp;ref=jenkins" style="width: 100%; min-height: 100vh; border: none"></iframe>
                 </div>
             </l:ajax>
         </l:main-panel>