fix(terminal): retain absent local shell display snapshots

application/state/sessionFactories.test.ts

@@ -4,7 +4,7 @@ import test from "node:test";
 import type { Host } from "../../domain/models";
 import { prepareSerialConfigForSavedHost } from "../../domain/serialBackspace";
 import { buildTelnetDeepLinkConnectionHost } from "../../domain/telnetDeepLink";
-import { resolveEffectiveTerminalHost } from "../../domain/terminalHostResolution";
+import { resolveEffectiveTerminalHost, resolveTerminalSessionHost } from "../../domain/terminalHostResolution";
 import {
   createHostTerminalSession,
   createSerialTerminalSession,
@@ -171,3 +171,16 @@ test("host session factories snapshot plugin connection configuration", () => {
   assert.deepEqual(workspace.pluginConnection, pluginConnection);
   assert.notEqual(workspace.pluginConnection, pluginConnection);
 });
+
+test("local sessions preserve intentionally absent display metadata when the saved shell changes", () => {
+  const original = host({ protocol: "local", hostname: "localhost", localShell: "/bin/bash" });
+  const source = createHostTerminalSession("original-bash", original);
+  const edited = { ...original, localShell: "/bin/zsh", localShellName: "Zsh", localShellIcon: "zsh" };
+  const copied = resolveTerminalSessionHost({ session: source, hosts: [edited], groupConfigs: [], proxyProfiles: [], localOs: "macos" });
+  assert.equal(copied.localShell, "/bin/bash");
+  assert.equal(copied.localShellName, "");
+  assert.equal(copied.localShellIcon, "");
+  const named = createHostTerminalSession("named-zsh", edited);
+  assert.equal(named.localShellName, "Zsh");
+  assert.equal(named.localShellIcon, "zsh");
+});

application/state/sessionFactories.ts

@@ -153,8 +153,8 @@ export const createHostTerminalSession = (
       // Preserve field presence: an edited host must not contribute its args
       // to a session that was launched with an explicit shell and no args.
       localShellArgs: host.localShellArgs ?? EMPTY_LOCAL_SHELL_ARGS,
-      localShellName: host.localShellName,
-      localShellIcon: host.localShellIcon,
+      localShellName: host.localShellName ?? "",
+      localShellIcon: host.localShellIcon ?? "",
       // Effective directory from resolveHostDefaultLocalShell, including a
       // Settings directory the saved host inherits. Copy Tab overlays this
       // snapshot, so a later settings or vault edit cannot move the relaunch.

components/top-tabs/TopTabItems.tsx

@@ -86,7 +86,7 @@ const SessionTabIcon: React.FC<{
   // Local protocol → shell-specific icon if available, else OS-specific icon
   if (protocol === 'local' || host?.protocol === 'local' || (!protocol && !host)) {
     // Use shell icon from discovery when available
-    const iconId = shellIcon || host?.localShellIcon;
+    const iconId = shellIcon ?? host?.localShellIcon;
     if (iconId) {
       return (
         <img

domain/sessionRestore.test.ts

@@ -875,3 +875,21 @@ test("restore retains an explicit backend-default local shell snapshot", () => {
   assert.deepEqual(restored.sessions[0].localShellArgs, []);
   assert.equal(restored.sessions[0].localStartDir, "~");
 });
+
+test("restore retains absent local display snapshots while legacy fields remain absent", () => {
+  const payload = buildSessionRestorePayload({
+    sessions: [
+      { ...session("empty-display"), protocol: "local", localShellName: "", localShellIcon: "" },
+      { ...session("named-display"), protocol: "local", localShellName: "Bash", localShellIcon: "bash" },
+      { ...session("legacy-display"), protocol: "local" },
+    ],
+    workspaces: [], tabOrder: [], activeTabId: "empty-display", now: 123,
+  });
+  const restored = sanitizeSessionRestorePayload(JSON.parse(JSON.stringify(payload)));
+  assert.equal(restored.sessions[0].localShellName, "");
+  assert.equal(restored.sessions[0].localShellIcon, "");
+  assert.equal(restored.sessions[1].localShellName, "Bash");
+  assert.equal(restored.sessions[1].localShellIcon, "bash");
+  assert.equal(restored.sessions[2].localShellName, undefined);
+  assert.equal(restored.sessions[2].localShellIcon, undefined);
+});

domain/sessionRestore.ts

@@ -154,8 +154,8 @@ const restoreSession = (session: TerminalSession): RestoredTerminalSession => {
     ...(serialConfig ? { serialConfig } : {}),
     ...(session.localShell !== undefined ? { localShell: session.localShell } : {}),
     ...(session.localShellArgs ? { localShellArgs: [...session.localShellArgs] } : {}),
-    ...(session.localShellName ? { localShellName: session.localShellName } : {}),
-    ...(session.localShellIcon ? { localShellIcon: session.localShellIcon } : {}),
+    ...(session.localShellName !== undefined ? { localShellName: session.localShellName } : {}),
+    ...(session.localShellIcon !== undefined ? { localShellIcon: session.localShellIcon } : {}),
     ...(session.localStartDir ? { localStartDir: session.localStartDir } : {}),
     ...(session.fontSize !== undefined ? { fontSize: session.fontSize } : {}),
     ...(session.fontSizeOverride !== undefined ? { fontSizeOverride: session.fontSizeOverride } : {}),
@@ -197,8 +197,8 @@ const restoreSessionFromUnknown = (value: unknown): RestoredTerminalSession | nu
     ...(serialConfig ? { serialConfig } : {}),
     ...(readStringAllowEmpty(value, "localShell") !== undefined ? { localShell: readStringAllowEmpty(value, "localShell") } : {}),
     ...(Array.isArray(value.localShellArgs) ? { localShellArgs: value.localShellArgs.filter((arg): arg is string => typeof arg === "string") } : {}),
-    ...(readString(value, "localShellName") ? { localShellName: readString(value, "localShellName") } : {}),
-    ...(readString(value, "localShellIcon") ? { localShellIcon: readString(value, "localShellIcon") } : {}),
+    ...(readStringAllowEmpty(value, "localShellName") !== undefined ? { localShellName: readStringAllowEmpty(value, "localShellName") } : {}),
+    ...(readStringAllowEmpty(value, "localShellIcon") !== undefined ? { localShellIcon: readStringAllowEmpty(value, "localShellIcon") } : {}),
     ...(readString(value, "localStartDir") ? { localStartDir: readString(value, "localStartDir") } : {}),
     ...(readNumber(value, "fontSize") !== undefined ? { fontSize: readNumber(value, "fontSize") } : {}),
     ...(readBoolean(value, "fontSizeOverride") !== undefined ? { fontSizeOverride: readBoolean(value, "fontSizeOverride") } : {}),