diff --git a/packages/source-control-core/src/server/pullRequestChecks.test.ts b/packages/source-control-core/src/server/pullRequestChecks.test.ts
index ba685083292449d6c8767db975c116c638fb0c5b..5033e719decb0a03ed67f5bc28507b4f9c8dfc91 100644
--- a/packages/source-control-core/src/server/pullRequestChecks.test.ts
+++ b/packages/source-control-core/src/server/pullRequestChecks.test.ts
@@ -50,6 +50,28 @@ describe("dedupeChecks", () => {
     ]);
   });
 
+  it("keeps distinct workflow and check pairs even when their names join to the same text", () => {
+    const checks = dedupeChecks([
+      entry("Linux tests", "success", {
+        workflowName: "Build",
+        at: "2026-08-11T16:00:00Z",
+      }),
+      entry("tests", "success", {
+        workflowName: "Build Linux",
+        at: "2026-08-11T17:00:00Z",
+      }),
+      entry("Linux tests", "failure", {
+        workflowName: "Build",
+        at: "2026-08-11T18:00:00Z",
+      }),
+    ]);
+
+    expect(checks.map((check) => [check.name, check.status])).toEqual([
+      ["Linux tests", "failure"],
+      ["tests", "success"],
+    ]);
+  });
+
   it("loses a run that never said when it happened to one that did, whichever came first", () => {
     const undated = dedupeChecks([
       entry("build", "success", { at: "2026-08-11T16:00:00Z" }),
diff --git a/packages/source-control-core/src/server/pullRequestChecks.ts b/packages/source-control-core/src/server/pullRequestChecks.ts
index 819cf47b01af485b83769c0c96f37f58d5769ae9..491b018032317af0eed6adea3973969611c78aca 100644
--- a/packages/source-control-core/src/server/pullRequestChecks.ts
+++ b/packages/source-control-core/src/server/pullRequestChecks.ts
@@ -36,7 +36,7 @@ export function dedupeChecks(
 ): ReadonlyArray<PullRequestCheck> {
   const newestByCheck = new Map<string, (typeof entries)[number]>();
   for (const entry of entries) {
-    const key = `${entry.workflowName ?? ""} ${entry.check.name}`;
+    const key = JSON.stringify([entry.workflowName ?? "", entry.check.name]);
     const kept = newestByCheck.get(key);
     // Re-setting a key a Map already holds keeps its first position, which is the order wanted.
     if (kept === undefined || isAtLeastAsNew(entry.at, kept.at)) newestByCheck.set(key, entry);