diff --git a/lib/platform/gitlab/index.spec.ts b/lib/platform/gitlab/index.spec.ts
index 72e26a2970a9031a1aef20144d5a76663d35c384..b4714de7ed8c136e96c8a3616867c9db517c4c1f 100644
--- a/lib/platform/gitlab/index.spec.ts
+++ b/lib/platform/gitlab/index.spec.ts
@@ -1870,6 +1870,16 @@ These updates have all been created already. Click a checkbox below to force a r
       expect(smartTruncate).toHaveBeenCalledTimes(1);
       expect(smartTruncate).toHaveBeenCalledWith(expect.any(String), 25000);
     });
+
+    it('truncates description for API version gt 13.4', async () => {
+      jest.mock('../utils/pr-body');
+      const { smartTruncate } = require('../utils/pr-body');
+
+      await initFakePlatform('13.4.1');
+      gitlab.massageMarkdown(prBody);
+      expect(smartTruncate).toHaveBeenCalledTimes(1);
+      expect(smartTruncate).toHaveBeenCalledWith(expect.any(String), 1000000);
+    });
   });
 
   describe('getVulnerabilityAlerts()', () => {
diff --git a/lib/platform/gitlab/index.ts b/lib/platform/gitlab/index.ts
index 43e82367b2cb5144a08220ac7464bc694dc91e81..97bb7e18cbc574200fd80355c8bcf3753d05b64e 100644
--- a/lib/platform/gitlab/index.ts
+++ b/lib/platform/gitlab/index.ts
@@ -685,6 +685,8 @@ export function massageMarkdown(input: string): string {
     );
 
     desc = smartTruncate(desc, 25000);
+  } else {
+    desc = smartTruncate(desc, 1000000);
   }
 
   return desc;