diff --git a/src/renderer/src/workspace/hook/actions/initialHistory.ts b/src/renderer/src/workspace/hook/actions/initialHistory.ts
index c19e84ac9..018a0cfb1 100644
--- a/src/renderer/src/workspace/hook/actions/initialHistory.ts
+++ b/src/renderer/src/workspace/hook/actions/initialHistory.ts
@@ -115,6 +115,12 @@ export async function loadInitialHistoryForSession({
     limit,
   })
 
+  // [xcript-diag #283] Trace the load lifecycle. The bug: this sets 'loading'
+  // unconditionally, but the terminal 'ready'/'error' below only land if the
+  // runtime entry still exists at resolve. If a rebuild/remap drops the key
+  // mid-load, the session is stuck at 'loading'. These warns make the timeline
+  // (and the exact drop) visible. REMOVE once root cause is fixed.
+  console.warn(`[xcript-diag] loading-set session=${sessionId} kind=${kind}`)
   setRuntimes(prev => {
     const current = prev[sessionId] ?? emptyRuntime()
     return {
@@ -142,7 +148,16 @@ export async function loadInitialHistoryForSession({
 
     setRuntimes(prev => {
       const current = prev[sessionId]
-      if (!current) return prev
+      if (!current) {
+        // [xcript-diag #283] SMOKING GUN: the load finished but the runtime
+        // entry for this id is gone, so the 'ready' write below is discarded
+        // and the pane stays stuck at 'loading'. Log which keys DO exist so we
+        // can see what it got remapped/rebuilt to.
+        console.warn(
+          `[xcript-diag] RESOLVE-DROPPED session=${sessionId} — runtime missing at resolve; 'ready' discarded (STUCK). liveKeys=[${Object.keys(prev).join(',')}]`,
+        )
+        return prev
+      }
       const seen = (refs.seenUuidsRef.current[sessionId] ??= new Set())
       seedSeenFromRuntime(current, seen)
 
@@ -274,6 +289,9 @@ export async function loadInitialHistoryForSession({
         },
       )
 
+      console.warn(
+        `[xcript-diag] ready-set session=${sessionId} entries=${initialEntries.length}`,
+      )
       return { ...prev, [sessionId]: nextRuntime }
     })
 
@@ -287,7 +305,12 @@ export async function loadInitialHistoryForSession({
     console.warn('[history] load initial failed', err)
     setRuntimes(prev => {
       const current = prev[sessionId]
-      if (!current) return prev
+      if (!current) {
+        console.warn(
+          `[xcript-diag] ERROR-DROPPED session=${sessionId} — runtime missing at error resolve; 'error' discarded (STUCK at 'loading'). msg=${message}`,
+        )
+        return prev
+      }
       return {
         ...prev,
         [sessionId]: {
diff --git a/src/renderer/src/workspace/hook/persistence/rehydrate.ts b/src/renderer/src/workspace/hook/persistence/rehydrate.ts
index c379f1b88..66d7a46e9 100644
--- a/src/renderer/src/workspace/hook/persistence/rehydrate.ts
+++ b/src/renderer/src/workspace/hook/persistence/rehydrate.ts
@@ -423,6 +423,19 @@ export async function rehydrateWorkspace(
             : true,
         }
       }
+      // [xcript-diag #283] commitRehydratedState is the ONLY wholesale runtimes
+      // rebuild (out = {}), so it is the prime suspect for dropping a key whose
+      // initial-history load is still in flight. Log any key present in `prev`
+      // but absent from `out` — especially one mid-'loading' — to confirm
+      // whether this commit is what orphans the loader's 'ready' write. REMOVE
+      // once root cause is fixed.
+      for (const [id, runtime] of Object.entries(prev)) {
+        if (!out[id]) {
+          console.warn(
+            `[xcript-diag] commitRehydrated DROPS session=${id} (was transcriptStatus=${runtime.transcriptStatus}); not in idMap/freshSessions`,
+          )
+        }
+      }
       return out
     })
     return true