Stage 400: PR #2709 — fix(model): prefer profile default model on fresh boot when localStorage has no persisted pick

Co-authored-by: starship-s <starship-s@users.noreply.github.com>

static/boot.js

@@ -1459,10 +1459,15 @@ function applyBotName(){
     if(s.default_model){
       window._defaultModel=s.default_model;
       const sel=$('modelSelect');
-      const savedState=(typeof _readPersistedModelState==='function')
-        ? _readPersistedModelState()
-        : (localStorage.getItem('hermes-webui-model')?{model:localStorage.getItem('hermes-webui-model'),model_provider:null}:null);
-      if(sel&&!savedState&&typeof _applyModelToDropdown==='function'){
+      if(sel&&typeof _applyModelToDropdown==='function'){
+        // Fresh page boot must prefer the profile/server default over stale
+        // browser-persisted model state. A restored session can still apply its
+        // own persisted model later through loadSession().
+        if(typeof _clearPersistedModelState==='function') _clearPersistedModelState();
+        else {
+          localStorage.removeItem('hermes-webui-model');
+          localStorage.removeItem('hermes-webui-model-state');
+        }
         const existingDefaultOpt=Array.from(sel.options).find(o=>o.value===s.default_model);
         if(existingDefaultOpt&&window._activeProvider&&!existingDefaultOpt.dataset.provider){
           existingDefaultOpt.dataset.provider=window._activeProvider;
@@ -1575,7 +1580,10 @@ function applyBotName(){
       ? _readPersistedModelState()
       : (localStorage.getItem('hermes-webui-model')?{model:localStorage.getItem('hermes-webui-model'),model_provider:null}:null);
     const savedModel=savedState&&savedState.model;
-    if(savedModel && $('modelSelect')){
+    // Guardrail: prefer profile/server default on boot when available.
+    // Persisted browser model state should not override a valid default model.
+    const allowBootSavedModelOverride=!window._defaultModel;
+    if(savedModel && $('modelSelect') && allowBootSavedModelOverride){
       const applied=(typeof _applyModelToDropdown==='function')
         ? _applyModelToDropdown(savedModel,$('modelSelect'),savedState.model_provider||null)
         : null;
@@ -1583,7 +1591,10 @@ function applyBotName(){
       // If the value didn't take (model not in list), clear the bad pref
       if(!applied&&$('modelSelect').value!==savedModel){
         if(typeof _clearPersistedModelState==='function') _clearPersistedModelState();
-        else localStorage.removeItem('hermes-webui-model');
+        else {
+          localStorage.removeItem('hermes-webui-model');
+          localStorage.removeItem('hermes-webui-model-state');
+        }
       }
       else if(typeof syncModelChip==='function') syncModelChip();
     }

static/ui.js

@@ -992,8 +992,10 @@ async function populateModelDropdown(){
       }
       sel.appendChild(og);
     }
-    // Set default model from server if no localStorage preference
-    if(data.default_model && !(typeof _readPersistedModelState==='function'&&_readPersistedModelState()) && !localStorage.getItem('hermes-webui-model')){
+    // Set default model from server on fresh/blank boot. Loaded sessions keep
+    // their own persisted model and apply it via loadSession(). Do not let stale
+    // browser localStorage suppress the profile default.
+    if(data.default_model && !(S.session&&S.session.model)){
       _applyModelToDropdown(data.default_model, sel, data.active_provider||null);
     }
     if(typeof syncModelChip==='function') syncModelChip();

tests/test_model_default_boot_precedence.py

@@ -0,0 +1,34 @@
+"""
+Regression coverage for model selector drift on fresh browser boot.
+
+A stale browser-persisted model (localStorage) must not suppress the configured
+profile/server default on page load. Restored sessions may still apply their own
+session model later through loadSession().
+"""
+from pathlib import Path
+
+
+REPO = Path(__file__).resolve().parents[1]
+BOOT_JS = (REPO / "static" / "boot.js").read_text(encoding="utf-8")
+UI_JS = (REPO / "static" / "ui.js").read_text(encoding="utf-8")
+
+
+def test_boot_settings_applies_default_even_when_browser_model_state_exists():
+    assert "Fresh page boot must prefer the profile/server default" in BOOT_JS
+    assert "_clearPersistedModelState" in BOOT_JS
+    assert "localStorage.removeItem('hermes-webui-model-state')" in BOOT_JS
+    assert "if(sel&&typeof _applyModelToDropdown==='function')" in BOOT_JS
+    assert "if(sel&&!savedState&&typeof _applyModelToDropdown==='function')" not in BOOT_JS
+
+
+def test_populate_model_dropdown_default_not_blocked_by_localstorage():
+    assert "Do not let stale\n    // browser localStorage suppress the profile default" in UI_JS
+    assert "if(data.default_model && !(S.session&&S.session.model))" in UI_JS
+    assert "_readPersistedModelState()" not in _populate_default_guard_snippet()
+    assert "localStorage.getItem('hermes-webui-model')" not in _populate_default_guard_snippet()
+
+
+def _populate_default_guard_snippet() -> str:
+    marker = "// Set default model from server on fresh/blank boot."
+    start = UI_JS.index(marker)
+    return UI_JS[start : start + 500]