diff --git a/src/renderer/src/lib/use-tab-agent.test.ts b/src/renderer/src/lib/use-tab-agent.test.ts
index 9152159f1..d2283db7d 100644
--- a/src/renderer/src/lib/use-tab-agent.test.ts
+++ b/src/renderer/src/lib/use-tab-agent.test.ts
@@ -258,6 +258,20 @@ describe('resolveTabAgentFromSignals', () => {
     ).toBe('claude')
   })
 
+  // Why: #8478 — OpenCode native `OC | …` titles must reclaim a stale Claude
+  // launch identity so the tab icon is OpenCode, not Claude.
+  it('uses OpenCode native session titles to replace stale Claude launch identity', () => {
+    expect(
+      resolveTabAgentFromSignals({
+        hasObservedAgentSignal: true,
+        isRemote: false,
+        title: 'OC | Understand about the plugin',
+        hookAgent: null,
+        launchAgent: 'claude'
+      })
+    ).toBe('opencode')
+  })
+
   it('does not let an explicit title override launch identity before any activity is observed', () => {
     expect(
       resolveTabAgentFromSignals({
diff --git a/src/renderer/src/runtime/sync-runtime-graph-terminal-layout.test.ts b/src/renderer/src/runtime/sync-runtime-graph-terminal-layout.test.ts
index 6095f4e18..385a7764f 100644
--- a/src/renderer/src/runtime/sync-runtime-graph-terminal-layout.test.ts
+++ b/src/renderer/src/runtime/sync-runtime-graph-terminal-layout.test.ts
@@ -16,6 +16,7 @@ function makeState(overrides: Partial<AppState> = {}): AppState {
     activeBrowserTabIdByWorktree: {},
     browserTabsByWorktree: {},
     browserPagesByWorkspace: {},
+    browserCertificateFailuresByPageId: {},
     openFiles: [],
     editorDrafts: {},
     activeTabId: null,
diff --git a/src/renderer/src/runtime/sync-runtime-graph.test.ts b/src/renderer/src/runtime/sync-runtime-graph.test.ts
index 2de176df7..d1082d89c 100644
--- a/src/renderer/src/runtime/sync-runtime-graph.test.ts
+++ b/src/renderer/src/runtime/sync-runtime-graph.test.ts
@@ -26,6 +26,7 @@ function makeState(overrides: Partial<AppState> = {}): AppState {
     activeBrowserTabIdByWorktree: {},
     browserTabsByWorktree: {},
     browserPagesByWorkspace: {},
+    browserCertificateFailuresByPageId: {},
     openFiles: [],
     editorDrafts: {},
     activeTabId: null,
@@ -60,6 +61,7 @@ function makeSharedOverrides(): Partial<AppState> {
     activeBrowserTabIdByWorktree: {},
     browserTabsByWorktree: {},
     browserPagesByWorkspace: {},
+    browserCertificateFailuresByPageId: {},
     openFiles: [],
     editorDrafts: {},
     agentStatusByPaneKey: {},
diff --git a/src/renderer/src/runtime/sync-runtime-graph.ts b/src/renderer/src/runtime/sync-runtime-graph.ts
index e735e1300..fb32a8479 100644
--- a/src/renderer/src/runtime/sync-runtime-graph.ts
+++ b/src/renderer/src/runtime/sync-runtime-graph.ts
@@ -1496,7 +1496,7 @@ function buildMobileBrowserTab(
     // back through ?? would resurrect a stale workspace-level error.
     loadError: activePage ? activePage.loadError : workspace.loadError,
     certificateFailure: activePage
-      ? (state.browserCertificateFailuresByPageId[activePage.id] ?? null)
+      ? (state.browserCertificateFailuresByPageId?.[activePage.id] ?? null)
       : null,
     color: unifiedTab?.color ?? null,
     isPinned: unifiedTab?.isPinned === true,
diff --git a/src/shared/agent-detection.ts b/src/shared/agent-detection.ts
index 891f37093..4fbfff86f 100644
--- a/src/shared/agent-detection.ts
+++ b/src/shared/agent-detection.ts
@@ -18,6 +18,7 @@ export {
   STRONG_IDLE_KEYWORDS_RE,
   STRONG_WORKING_KEYWORDS_RE
 } from './agent-title-core'
+export { isOpenCodeNativeTitle, isMeaningfulOpenCodeTerminalTitle } from './opencode-terminal-title'
 export { getAgentLabel, isClaudeAgent } from './agent-title-identity'
 export {
   clearWorkingIndicators,
diff --git a/src/shared/agent-title-identity.ts b/src/shared/agent-title-identity.ts
index 9f7746b01..af86de166 100644
--- a/src/shared/agent-title-identity.ts
+++ b/src/shared/agent-title-identity.ts
@@ -10,6 +10,7 @@ import {
   isPiAgentTitle,
   titleHasAgentName
 } from './agent-title-core'
+import { isOpenCodeNativeTitle } from './opencode-terminal-title'
 import { getPiCompatibleSyntheticAgentLabel } from './pi-compatible-synthetic-title'
 
 /**
@@ -17,7 +18,7 @@ import { getPiCompatibleSyntheticAgentLabel } from './pi-compatible-synthetic-ti
  * Used to scope prompt-cache-timer behavior to Claude sessions only.
  */
 export function isClaudeAgent(title: string): boolean {
-  if (!title || isClaudeManagementTitle(title)) {
+  if (!title || isClaudeManagementTitle(title) || isOpenCodeNativeTitle(title)) {
     return false
   }
   const lower = title.toLowerCase()
@@ -46,6 +47,11 @@ export function getAgentLabel(title: string): string | null {
   if (isClaudeManagementTitle(title)) {
     return null
   }
+  // Why: the native marker owns the whole title; its session text may name or
+  // include status glyphs from other agents without changing OpenCode identity.
+  if (isOpenCodeNativeTitle(title)) {
+    return 'OpenCode'
+  }
   // Why: Claude task titles can mention another CLI; the prefix is the identity
   // signal, not arbitrary task text.
   if (
diff --git a/src/shared/opencode-terminal-title.test.ts b/src/shared/opencode-terminal-title.test.ts
index fc1b7806e..f1cb825e8 100644
--- a/src/shared/opencode-terminal-title.test.ts
+++ b/src/shared/opencode-terminal-title.test.ts
@@ -1,16 +1,23 @@
 import { describe, expect, it } from 'vitest'
-import { isMeaningfulOpenCodeTerminalTitle } from './opencode-terminal-title'
+import { isMeaningfulOpenCodeTerminalTitle, isOpenCodeNativeTitle } from './opencode-terminal-title'
 
 describe('OpenCode terminal titles', () => {
   it('recognizes native session titles', () => {
     expect(isMeaningfulOpenCodeTerminalTitle('OC | Native Stable Session')).toBe(true)
     expect(isMeaningfulOpenCodeTerminalTitle('  OC|Session  ')).toBe(true)
+    expect(isOpenCodeNativeTitle('OC | Understand about the plugin')).toBe(true)
+    expect(isOpenCodeNativeTitle('tmux | OC | ses_123')).toBe(true)
   })
 
-  it('rejects generic or incomplete OpenCode titles', () => {
+  it('rejects generic, incomplete, embedded, and lookalike titles', () => {
     expect(isMeaningfulOpenCodeTerminalTitle('OpenCode')).toBe(false)
     expect(isMeaningfulOpenCodeTerminalTitle('OpenCode ready')).toBe(false)
     expect(isMeaningfulOpenCodeTerminalTitle('OC |')).toBe(false)
     expect(isMeaningfulOpenCodeTerminalTitle(undefined)).toBe(false)
+    // Why: lowercase is not OpenCode's native marker; avoid "oc |" cwd/task noise.
+    expect(isOpenCodeNativeTitle('oc | Understand about the plugin')).toBe(false)
+    // Why: mid-title OC must not steal another agent's braille/task frame.
+    expect(isOpenCodeNativeTitle('⠋ Fix foo | OC | bar')).toBe(false)
+    expect(isOpenCodeNativeTitle('my session | OC | task')).toBe(false)
   })
 })
diff --git a/src/shared/opencode-terminal-title.ts b/src/shared/opencode-terminal-title.ts
index 64312b94b..01d3d3819 100644
--- a/src/shared/opencode-terminal-title.ts
+++ b/src/shared/opencode-terminal-title.ts
@@ -1,4 +1,14 @@
-export function isMeaningfulOpenCodeTerminalTitle(title: string | null | undefined): boolean {
-  // Why: bare OpenCode labels are status/identity; `OC | …` carries native session identity.
-  return /^OC\s*\|\s*\S/u.test(title?.trim() ?? '')
+// Why: OpenCode abbreviates native OSC session titles as `OC | <task>` (no
+// agent-name token). Optional single-token multiplexer prefix covers SSH/tmux
+// frames like `tmux | OC | …`. Case-sensitive `OC` avoids ordinary lowercase
+// "oc" lookalikes; require non-whitespace after the marker so bare `OC |` is not
+// identity. Used for both display-title preservation and tab-agent identity.
+const OPENCODE_NATIVE_TITLE_RE = /^(?:[^|\s]+ \| )?OC\s*\|\s*\S/u
+
+export function isOpenCodeNativeTitle(title: string | null | undefined): boolean {
+  return OPENCODE_NATIVE_TITLE_RE.test(title?.trim() ?? '')
+}
+
+export function isMeaningfulOpenCodeTerminalTitle(title: string | null | undefined): boolean {
+  return isOpenCodeNativeTitle(title)
 }
diff --git a/src/shared/repro-8478-opencode-native-title-icon.test.ts b/src/shared/repro-8478-opencode-native-title-icon.test.ts
new file mode 100644
index 000000000..554ac0c5d
--- /dev/null
+++ b/src/shared/repro-8478-opencode-native-title-icon.test.ts
@@ -0,0 +1,49 @@
+/**
+ * Issue #8478 — OpenCode logo / icon not coming up well (Claude glyph on
+ * OpenCode tabs).
+ *
+ * Root cause (pre-fix): OpenCode's native OSC tab title format is `OC | <task>`.
+ * Title classifiers only recognized OpenCode when the token "opencode" appeared.
+ * Native `OC | …` titles fell through, so AgentIcon rendered Claude/"?".
+ *
+ * OpenCode source (packages/tui/src/app.tsx) sets titles as:
+ *   - "OpenCode" on home / default session titles
+ *   - `OC | ${title}` for named sessions (title truncated at 40 chars)
+ *   - `OC | ${pluginId}` on plugin routes
+ *
+ * Related: #8940 (OpenCode activity frames mislabeled Claude Code — separate
+ * braille-without-token path; not fully solved here).
+ *
+ * Re-run:
+ *   pnpm exec vitest run --config config/vitest.config.ts \
+ *     src/shared/repro-8478-opencode-native-title-icon.test.ts
+ */
+import { describe, expect, it } from 'vitest'
+import { getAgentLabel, isClaudeAgent } from './agent-detection'
+import {
+  resolveExplicitTerminalTitleAgentType,
+  resolveTerminalTitleAgentType
+} from './terminal-title-agent-type'
+
+describe('#8478 OpenCode native OC | titles map to OpenCode icon', () => {
+  it('recognizes OpenCode native "OC | …" title format as opencode identity', () => {
+    const native = 'OC | Understand about the plugin'
+    expect(getAgentLabel(native)).toBe('OpenCode')
+    expect(resolveTerminalTitleAgentType(native)).toBe('opencode')
+    expect(resolveExplicitTerminalTitleAgentType(native)).toBe('opencode')
+    expect(isClaudeAgent(native)).toBe(false)
+  })
+
+  // Why: bare "OpenCode" is what the TUI sets on home/default sessions; keep it
+  // classified so the icon path stays OpenCode without the OC | abbreviation.
+  it('keeps bare OpenCode home titles and Claude-style frames classified correctly', () => {
+    expect(getAgentLabel('OpenCode')).toBe('OpenCode')
+    expect(resolveTerminalTitleAgentType('OpenCode')).toBe('opencode')
+    expect(getAgentLabel('OpenCode ready')).toBe('OpenCode')
+    expect(resolveTerminalTitleAgentType('OpenCode ready')).toBe('opencode')
+    // Same family as #8940: braille/task frames without "opencode" still become Claude
+    // when they lack the native OC marker — documented, out of scope for this fix.
+    expect(isClaudeAgent('⠋ implementing the feature')).toBe(true)
+    expect(getAgentLabel('⠋ implementing the feature')).toBe('Claude Code')
+  })
+})
diff --git a/src/shared/terminal-title-agent-type.test.ts b/src/shared/terminal-title-agent-type.test.ts
index d28dd43f5..d0fda7dcc 100644
--- a/src/shared/terminal-title-agent-type.test.ts
+++ b/src/shared/terminal-title-agent-type.test.ts
@@ -1,4 +1,6 @@
 import { describe, expect, it } from 'vitest'
+import { getAgentLabel as getSharedAgentLabel } from './agent-title-identity'
+import { isOpenCodeNativeTitle } from './opencode-terminal-title'
 import {
   isClaudeAgent,
   isGrokRotatingWorkingTitle,
@@ -51,6 +53,39 @@ describe('resolveExplicitTerminalTitleAgentType', () => {
     expect(resolveExplicitTerminalTitleAgentType('* Review Codex behavior')).toBeNull()
   })
 
+  it('resolves OpenCode native abbreviated session titles before task-text identities', () => {
+    expect(resolveExplicitTerminalTitleAgentType('OC | Understand about the plugin')).toBe(
+      'opencode'
+    )
+    expect(resolveExplicitTerminalTitleAgentType('OC | Compare Codex and Claude')).toBe('opencode')
+    // Why: Gemini glyphs inside OpenCode session text must not rebrand the tab.
+    expect(resolveExplicitTerminalTitleAgentType('OC | ✦ Gemini CLI')).toBe('opencode')
+    expect(getSharedAgentLabel('OC | Compare Codex and Claude')).toBe('OpenCode')
+    expect(getSharedAgentLabel('OC | ✦ Gemini CLI')).toBe('OpenCode')
+    expect(resolveExplicitTerminalTitleAgentType('tmux | OC | ses_123')).toBe('opencode')
+    expect(resolveExplicitTerminalTitleAgentType('OC|compact-session')).toBe('opencode')
+    expect(resolveExplicitTerminalTitleAgentType('oc | Understand about the plugin')).toBeNull()
+  })
+
+  it('does not find an OpenCode marker inside another agent task title', () => {
+    expect(isOpenCodeNativeTitle('⠋ Fix foo | OC | bar')).toBe(false)
+    expect(resolveExplicitTerminalTitleAgentType('⠋ Fix foo | OC | bar')).toBeNull()
+  })
+
+  // Why: adversarial coverage — native OC must not steal Claude/Codex/Cursor/
+  // Gemini/Pi identity, and those agents must keep resolving when titled normally.
+  it('keeps other agents classified correctly alongside OpenCode native titles', () => {
+    expect(resolveExplicitTerminalTitleAgentType('✳ Claude Code')).toBe('claude')
+    expect(resolveExplicitTerminalTitleAgentType('⠋ Codex')).toBe('codex')
+    expect(resolveExplicitTerminalTitleAgentType('✦ Gemini CLI')).toBe('gemini')
+    expect(resolveExplicitTerminalTitleAgentType('Cursor Agent')).toBe('cursor')
+    expect(resolveExplicitTerminalTitleAgentType('Pi ready')).toBe('pi')
+    expect(resolveExplicitTerminalTitleAgentType('OpenCode ready')).toBe('opencode')
+    expect(resolveTerminalTitleAgentType('OC | ⠋ implementing the feature')).toBe('opencode')
+    expect(isClaudeAgent('OC | ⠋ implementing the feature')).toBe(false)
+    expect(isClaudeAgent('OC | Understand about the plugin')).toBe(false)
+  })
+
   it('still resolves Claude when the title explicitly names Claude', () => {
     expect(resolveExplicitTerminalTitleAgentType('. Claude Code compare Opencode')).toBe('claude')
   })
diff --git a/src/shared/terminal-title-agent-type.ts b/src/shared/terminal-title-agent-type.ts
index ae7c97c09..fa92bb198 100644
--- a/src/shared/terminal-title-agent-type.ts
+++ b/src/shared/terminal-title-agent-type.ts
@@ -5,6 +5,7 @@ import {
   titleHasAgentName
 } from './agent-name-token-match'
 import { isCursorAgentTitle } from './agent-title-core'
+import { isOpenCodeNativeTitle } from './opencode-terminal-title'
 import {
   getPiCompatibleSyntheticAgentLabel,
   isLegacyPiCompatibleTitle
@@ -80,7 +81,7 @@ export function isPiAgentTitle(title: string): boolean {
  * agents have different (or no) caching semantics.
  */
 export function isClaudeAgent(title: string): boolean {
-  if (!title || isClaudeManagementTitle(title)) {
+  if (!title || isClaudeManagementTitle(title) || isOpenCodeNativeTitle(title)) {
     return false
   }
   const lower = title.toLowerCase()
@@ -124,6 +125,11 @@ export function getAgentLabel(title: string): string | null {
   if (isClaudeManagementTitle(title)) {
     return null
   }
+  // Why: the native marker owns the whole title; its session text may name or
+  // include status glyphs from other agents without changing OpenCode identity.
+  if (isOpenCodeNativeTitle(title)) {
+    return 'OpenCode'
+  }
   // Why: Claude Code title text is often the task title. If that task mentions
   // another CLI, the Claude-specific prefix is the identity signal, not the words.
   if (