diff --git a/src/main/java/org/jenkinsci/plugins/github_branch_source/ForkPullRequestDiscoveryTrait.java b/src/main/java/org/jenkinsci/plugins/github_branch_source/ForkPullRequestDiscoveryTrait.java
index f7bf3e7d0..495380b21 100644
--- a/src/main/java/org/jenkinsci/plugins/github_branch_source/ForkPullRequestDiscoveryTrait.java
+++ b/src/main/java/org/jenkinsci/plugins/github_branch_source/ForkPullRequestDiscoveryTrait.java
@@ -39,7 +39,6 @@
 import jenkins.scm.api.trait.SCMHeadAuthority;
 import jenkins.scm.api.trait.SCMHeadAuthorityDescriptor;
 import jenkins.scm.api.trait.SCMSourceContext;
-import jenkins.scm.api.trait.SCMSourceRequest;
 import jenkins.scm.api.trait.SCMSourceTrait;
 import jenkins.scm.api.trait.SCMSourceTraitDescriptor;
 import jenkins.scm.impl.ChangeRequestSCMHeadCategory;
@@ -83,6 +82,12 @@ public class ForkPullRequestDiscoveryTrait extends SCMSourceTrait {
      * @param trust the authority to use.
      */
     @DataBoundConstructor
+    public ForkPullRequestDiscoveryTrait(int strategyId, @NonNull GitHubForkTrustPolicy trust) {
+        this.strategyId = strategyId;
+        this.trust = trust;
+    }
+
+    @Deprecated
     public ForkPullRequestDiscoveryTrait(
             int strategyId,
             @NonNull
@@ -236,9 +241,15 @@ public List<SCMHeadAuthorityDescriptor> getTrustDescriptors() {
         }
     }
 
+    /** Trust policy for forked pull requests.
+     * <p>
+     * This reduces generics in the DataBoundConstructor signature as a workaround for JENKINS-26535.
+     */
+    public abstract static class GitHubForkTrustPolicy
+            extends SCMHeadAuthority<GitHubSCMSourceRequest, PullRequestSCMHead, PullRequestSCMRevision> {}
+
     /** An {@link SCMHeadAuthority} that trusts nothing. */
-    public static class TrustNobody
-            extends SCMHeadAuthority<SCMSourceRequest, PullRequestSCMHead, PullRequestSCMRevision> {
+    public static class TrustNobody extends GitHubForkTrustPolicy {
 
         /** Constructor. */
         @DataBoundConstructor
@@ -246,7 +257,7 @@ public TrustNobody() {}
 
         /** {@inheritDoc} */
         @Override
-        public boolean checkTrusted(@NonNull SCMSourceRequest request, @NonNull PullRequestSCMHead head) {
+        public boolean checkTrusted(@NonNull GitHubSCMSourceRequest request, @NonNull PullRequestSCMHead head) {
             return false;
         }
 
@@ -270,8 +281,7 @@ public boolean isApplicableToOrigin(@NonNull Class<? extends SCMHeadOrigin> orig
     }
 
     /** An {@link SCMHeadAuthority} that trusts contributors to the repository. */
-    public static class TrustContributors
-            extends SCMHeadAuthority<GitHubSCMSourceRequest, PullRequestSCMHead, PullRequestSCMRevision> {
+    public static class TrustContributors extends GitHubForkTrustPolicy {
         /** Constructor. */
         @DataBoundConstructor
         public TrustContributors() {}
@@ -303,8 +313,7 @@ public boolean isApplicableToOrigin(@NonNull Class<? extends SCMHeadOrigin> orig
     }
 
     /** An {@link SCMHeadAuthority} that trusts those with write permission to the repository. */
-    public static class TrustPermission
-            extends SCMHeadAuthority<GitHubSCMSourceRequest, PullRequestSCMHead, PullRequestSCMRevision> {
+    public static class TrustPermission extends GitHubForkTrustPolicy {
 
         /** Constructor. */
         @DataBoundConstructor
@@ -347,15 +356,14 @@ public boolean isApplicableToOrigin(@NonNull Class<? extends SCMHeadOrigin> orig
     }
 
     /** An {@link SCMHeadAuthority} that trusts everyone. */
-    public static class TrustEveryone
-            extends SCMHeadAuthority<SCMSourceRequest, PullRequestSCMHead, PullRequestSCMRevision> {
+    public static class TrustEveryone extends GitHubForkTrustPolicy {
         /** Constructor. */
         @DataBoundConstructor
         public TrustEveryone() {}
 
         /** {@inheritDoc} */
         @Override
-        protected boolean checkTrusted(@NonNull SCMSourceRequest request, @NonNull PullRequestSCMHead head) {
+        protected boolean checkTrusted(@NonNull GitHubSCMSourceRequest request, @NonNull PullRequestSCMHead head) {
             return true;
         }
 
diff --git a/src/test/java/org/jenkinsci/plugins/github_branch_source/ForkPullRequestDiscoveryTrait2Test.java b/src/test/java/org/jenkinsci/plugins/github_branch_source/ForkPullRequestDiscoveryTrait2Test.java
index 91ef0c4d5..cb61162c6 100644
--- a/src/test/java/org/jenkinsci/plugins/github_branch_source/ForkPullRequestDiscoveryTrait2Test.java
+++ b/src/test/java/org/jenkinsci/plugins/github_branch_source/ForkPullRequestDiscoveryTrait2Test.java
@@ -28,9 +28,6 @@
 import java.util.Collections;
 import java.util.List;
 import jenkins.branch.BranchSource;
-import jenkins.scm.api.SCMRevision;
-import jenkins.scm.api.mixin.ChangeRequestSCMHead2;
-import jenkins.scm.api.trait.SCMHeadAuthority;
 import jenkins.scm.api.trait.SCMSourceTrait;
 import org.jenkinsci.plugins.workflow.multibranch.WorkflowMultiBranchProject;
 import org.junit.Ignore;
@@ -69,8 +66,7 @@ public void configRoundtripWithRawUrl() throws Exception {
 
     private void assertRoundTrip(
             WorkflowMultiBranchProject p,
-            SCMHeadAuthority<? super GitHubSCMSourceRequest, ? extends ChangeRequestSCMHead2, ? extends SCMRevision>
-                    trust,
+            ForkPullRequestDiscoveryTrait.GitHubForkTrustPolicy trust,
             boolean configuredByUrl)
             throws Exception {