diff --git a/apps/presentation/dashboard/src/views/dashboard-page.tsx b/apps/presentation/dashboard/src/views/dashboard-page.tsx
index 6054750162..ea409513be 100644
--- a/apps/presentation/dashboard/src/views/dashboard-page.tsx
+++ b/apps/presentation/dashboard/src/views/dashboard-page.tsx
@@ -3654,7 +3654,9 @@ export function DashboardPage() {
   }, [exampleModeRequested, requestedStatusUrl, search.statusUrl, search.rootGoalId, source.kind, source.label]);
 
   useEffect(() => {
-    if (isLoading && search.rootGoalId) return;
+    // A source transition can still expose the previous source's Goal rows.
+    // Reconcile only its committed URL, including during browser Back/Forward.
+    if (isLoading || (source.kind === "url" && search.statusUrl && search.statusUrl !== source.label)) return;
     if (search.statusUrl && source.kind === "example") {
       return;
     }
@@ -3662,6 +3664,7 @@ export function DashboardPage() {
     if (goalRows.length === 0) {
       if (search.goalId) {
         void navigate({
+          replace: true,
           search: (current) => ({
             ...current,
             goalId: "",
@@ -3673,13 +3676,14 @@ export function DashboardPage() {
     if (search.goalId && !goalIds.has(search.goalId)
       && goalArchiveLoadState.phase !== "loading") {
       void navigate({
+        replace: true,
         search: (current) => ({
           ...current,
           goalId: "",
         }),
       });
     }
-  }, [goalArchiveLoadState.phase, goalRows, isLoading, navigate, search.goalId, search.rootGoalId, search.statusUrl, source.kind]);
+  }, [goalArchiveLoadState.phase, goalRows, isLoading, navigate, search.goalId, search.rootGoalId, search.statusUrl, source.kind, source.label]);
 
   useEffect(() => {
     if (!progress || isLoading || !search.goalId || source.kind !== "url") return;
diff --git a/examples/personal-workspace-browser/evidence/source-history-return/before-desktop.png b/examples/personal-workspace-browser/evidence/source-history-return/before-desktop.png
new file mode 100644
index 0000000000..bdbb1f3760
Binary files /dev/null and b/examples/personal-workspace-browser/evidence/source-history-return/before-desktop.png differ
diff --git a/examples/personal-workspace-browser/evidence/source-history-return/desktop.png b/examples/personal-workspace-browser/evidence/source-history-return/desktop.png
new file mode 100644
index 0000000000..1421572f77
Binary files /dev/null and b/examples/personal-workspace-browser/evidence/source-history-return/desktop.png differ
diff --git a/examples/personal-workspace-browser/evidence/source-history-return/phone.png b/examples/personal-workspace-browser/evidence/source-history-return/phone.png
new file mode 100644
index 0000000000..e3752c3667
Binary files /dev/null and b/examples/personal-workspace-browser/evidence/source-history-return/phone.png differ
diff --git a/examples/personal-workspace-browser/runtime-source-workspace-browser-smoke.mjs b/examples/personal-workspace-browser/runtime-source-workspace-browser-smoke.mjs
index 80aec64612..425af3fbca 100644
--- a/examples/personal-workspace-browser/runtime-source-workspace-browser-smoke.mjs
+++ b/examples/personal-workspace-browser/runtime-source-workspace-browser-smoke.mjs
@@ -19,7 +19,8 @@ from loopx.control_plane.status.goal_source import GoalSource
 from loopx.capabilities.explore.result_log import build_explore_node_event, build_explore_edge_event
 class Source(GoalSource):
     def __init__(self, name):
-        super().__init__(name,name,'/registry','/runtime','/cli','/python','/bin','local','host','same-goal')
+        goal_id = 'other-goal' if name == 'Distinct' else 'same-goal'
+        super().__init__(name,name,'/registry','/runtime','/cli','/python','/bin','local','host',goal_id)
     def read_status(self, goal_id=None):
         self.check_access(goal_id)
         if pathlib.Path(sys.argv[1]).exists() and self.id == 'Fresh': raise OSError('unavailable fixture')
@@ -37,7 +38,7 @@ class Source(GoalSource):
         events += [build_explore_edge_event(goal_id=self.goal_id,from_node='route'+str(i),to_node='route'+str(i+1),edge_type='depends_on',recorded_at='2026-01-01T23:%02d:00Z'%(i*30)) for i in range(2)]
         return events
 assets=pathlib.Path(sys.argv[2])
-servers=[RuntimeWorkspaceServer(Source(n),assets) for n in ('Retained','Fresh')]
+servers=[RuntimeWorkspaceServer(Source(n),assets) for n in ('Retained','Fresh','Distinct')]
 catalog=[dict(id=s.source.id,label=s.source.label,status_url=s.status_url) for s in servers]
 for s in servers:
     s.catalog=catalog
@@ -92,6 +93,36 @@ try {
     await page.locator(".research-history-coverage").filter({hasText:"92 / 92"}).waitFor();
     await page.goBack();
     await page.getByRole("heading",{name:"Retained research",exact:true}).waitFor();
+    // Different Goal ids exercise automatic selection cleanup as well as the
+    // source-local node fence above. Cleanup must not rewrite the old source's
+    // entry or add an extra entry that traps Back/Forward on the new source.
+    await page.getByLabel("选择控制面来源",{exact:true}).click();
+    await page.getByRole("option",{name:"Distinct",exact:true}).click();
+    await page.getByRole("button",{name:/Distinct research/}).first().waitFor();
+    await page.waitForFunction(()=>new URL(location.href).searchParams.get("goalId")==="");
+    await page.goBack();
+    await page.getByRole("heading",{name:"Retained research",exact:true}).waitFor({timeout:10000});
+    assert.equal(new URL(page.url()).searchParams.get("goalId"),"same-goal");
+    assert.equal(new URL(page.url()).searchParams.get("research_node"),"route0");
+    await page.screenshot({path:resolve(output,"source-return-desktop.png")});
+    await page.goForward();
+    await page.getByRole("button",{name:/Distinct research/}).first().waitFor();
+    await page.getByRole("button",{name:/Distinct research/}).first().click();
+    await page.getByRole("heading",{name:"Distinct research",exact:true}).waitFor();
+    assert.equal(new URL(page.url()).searchParams.get("goalId"),"other-goal");
+    await page.reload();
+    await page.getByRole("heading",{name:"Distinct research",exact:true}).waitFor();
+    await page.getByLabel("选择控制面来源",{exact:true}).click();
+    await page.getByRole("option",{name:"Retained",exact:true}).click();
+    await page.getByRole("button",{name:/Retained research/}).first().waitFor();
+    await page.waitForFunction(()=>new URL(location.href).searchParams.get("goalId")==="");
+    await page.goBack();
+    await page.getByRole("heading",{name:"Distinct research",exact:true}).waitFor({timeout:10000});
+    assert.equal(new URL(page.url()).searchParams.get("goalId"),"other-goal");
+    await page.goForward();
+    await page.getByRole("button",{name:/Retained research/}).first().waitFor();
+    await page.getByRole("button",{name:/Retained research/}).first().click();
+    await page.getByRole("heading",{name:"Retained research",exact:true}).waitFor();
     await writeFile(failFile, "unavailable");
     for (let attempt=0;attempt<40;attempt++) {
       if ((await fetch(catalog[1].status_url)).status === 503) break;