diff --git a/CHANGELOG.md b/CHANGELOG.md
index c6bb692..bb393ca 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -14,17 +14,12 @@ All notable changes to Claude Code Studio will be documented in this file.
 - Composer UX improvements — expand toggle, drag handle, line/char count (84e2296)
 - Notes pad replaces Inbox tab in right pane (7354643)
 - Collapsible left sidebar with Ctrl+B shortcut (21f7363)
-- Plugin system with MCP-based architecture (e14a91c)
 - Drag-and-drop between panes via toolbar handle (757984a)
 
 ### Fixed
 - Preserve claudeSessionId across app restarts for session recovery (f4a3a57)
 - Japanese input and multiline text with bracketed paste (21ed2f1)
-- SSH+tmux session reconnection with claude lifecycle management (8575494)
 - Remove bottom gap in ActivityMap/ConfigMap, responsive stats cards (a886cf2)
-- Security hardening, lint fixes, remove bundled Aurelius plugin (3302f5a)
-- TitleBar platform-aware padding, Linux repaint cleanup (751917f)
-- Linux GPU stability — SIGSEGV fix, titlebar overlay crash fix (5e01a4c)
 
 ### Documentation
 - Screenshots added to README (be103b8)
diff --git a/src/main/plugins/__tests__/pluginEnvFilter.test.ts b/src/main/plugins/__tests__/pluginEnvFilter.test.ts
index f65e86a..2ee6753 100644
--- a/src/main/plugins/__tests__/pluginEnvFilter.test.ts
+++ b/src/main/plugins/__tests__/pluginEnvFilter.test.ts
@@ -142,4 +142,18 @@ describe('filterEnvForPlugin', () => {
     const result = filterEnvForPlugin({})
     expect(Object.keys(result)).toHaveLength(0)
   })
+
+  it('blocks API_KEY variants without $ anchor (e.g. SOME_API_KEY_FILE)', () => {
+    const env: NodeJS.ProcessEnv = {
+      SOME_API_KEY_FILE: '/path/to/key',
+      MY_API_KEY_PATH: '/another/path',
+      API_KEY_ROTATION_DATE: '2026-01-01',
+      PATH: '/usr/bin'
+    }
+    const result = filterEnvForPlugin(env)
+    expect(result.SOME_API_KEY_FILE).toBeUndefined()
+    expect(result.MY_API_KEY_PATH).toBeUndefined()
+    expect(result.API_KEY_ROTATION_DATE).toBeUndefined()
+    expect(result.PATH).toBe('/usr/bin')
+  })
 })
diff --git a/src/main/plugins/pluginEnvFilter.ts b/src/main/plugins/pluginEnvFilter.ts
index 08e3ccb..5e64506 100644
--- a/src/main/plugins/pluginEnvFilter.ts
+++ b/src/main/plugins/pluginEnvFilter.ts
@@ -66,7 +66,7 @@ const SENSITIVE_PATTERNS = [
   /password/i,
   /private.?key/i,
   /auth.?token/i,
-  /api.?key$/i,
+  /api.?key/i,
   /credentials/i,
   /access.?key/i
 ]
diff --git a/src/main/plugins/pluginManager.ts b/src/main/plugins/pluginManager.ts
index 16cb665..12695b3 100644
--- a/src/main/plugins/pluginManager.ts
+++ b/src/main/plugins/pluginManager.ts
@@ -42,6 +42,11 @@ export class PluginManager {
       paths.push(join(home, 'AppData', 'Local', 'Programs'))
       paths.push(join(home, 'AppData', 'Local', 'claude-code-studio', 'plugins'))
     }
+    if (process.platform === 'darwin') {
+      paths.push('/usr/local/bin')
+      paths.push('/opt/homebrew/bin')
+      paths.push(join(home, 'Library', 'Application Support', 'claude-code-studio', 'plugins'))
+    }
     // Normalize separators for consistent startsWith comparison
     return paths.map((p) => p.replace(/\\/g, '/'))
   }
@@ -137,6 +142,14 @@ export class PluginManager {
     const localBin = join(homedir(), '.local', 'bin', cmd)
     if (existsSync(localBin)) return true
 
+    // Check macOS-specific paths (Homebrew)
+    if (process.platform === 'darwin') {
+      const homebrewBin = join('/opt/homebrew/bin', cmd)
+      if (existsSync(homebrewBin)) return true
+      const usrLocalBin = join('/usr/local/bin', cmd)
+      if (existsSync(usrLocalBin)) return true
+    }
+
     // Check PATH (cross-platform)
     try {
       const whichCmd = process.platform === 'win32' ? 'where' : 'which'
@@ -162,6 +175,14 @@ export class PluginManager {
     const localBin = join(homedir(), '.local', 'bin', cmd)
     if (existsSync(localBin)) return localBin
 
+    // Check macOS-specific paths (Homebrew)
+    if (process.platform === 'darwin') {
+      const homebrewBin = join('/opt/homebrew/bin', cmd)
+      if (existsSync(homebrewBin)) return homebrewBin
+      const usrLocalBin = join('/usr/local/bin', cmd)
+      if (existsSync(usrLocalBin)) return usrLocalBin
+    }
+
     // Fall back to PATH
     return cmd
   }
@@ -177,7 +198,8 @@ export class PluginManager {
     const args = entry.manifest.mcp.args
 
     const filteredEnv = filterEnvForPlugin(process.env)
-    const pluginEnv = extraEnvVars ? { ...filteredEnv, ...extraEnvVars } : filteredEnv
+    const filteredExtra = extraEnvVars ? filterEnvForPlugin(extraEnvVars as NodeJS.ProcessEnv) : undefined
+    const pluginEnv = filteredExtra ? { ...filteredEnv, ...filteredExtra } : filteredEnv
 
     const proc = spawn(command, args, {
       stdio: ['pipe', 'pipe', 'pipe'],
diff --git a/src/main/utils.ts b/src/main/utils.ts
index fbe3b0c..850239b 100644
--- a/src/main/utils.ts
+++ b/src/main/utils.ts
@@ -5,6 +5,9 @@ export function stripAnsiCodes(str: string): string {
     .replace(/\x1B\][^\x07]*\x07/g, '')               // OSC sequences
     .replace(/\x1B[()][0-9A-B]/g, '')                  // Character set selection
     .replace(/\x1B[\x20-\x2F]*[\x30-\x7E]/g, '')      // Other ESC sequences
-    .replace(/O\?[\d;]*c/g, '')                        // Orphaned DA responses (ESC lost at chunk boundary)
+    // Orphaned Device Attributes (DA) response: terminals reply with ESC[?1;2c etc.
+    // When output is chunked, the leading ESC may land in a previous chunk, leaving
+    // only the tail "O?<digits>c" in the current one. Strip it to avoid UI noise.
+    .replace(/O\?[\d;]*c/g, '')
 }
 /* eslint-enable no-control-regex */
diff --git a/src/shared/types.ts b/src/shared/types.ts
index 116bfd0..4ca4ff0 100644
--- a/src/shared/types.ts
+++ b/src/shared/types.ts
@@ -593,6 +593,7 @@ export interface PluginManifest {
     toolbarButtons: { id: string; tool: string; icon: string; prompt: string }[]
     contextTab?: { id: string; label: string; icon: string; component: string }
   }
+  permissions?: PluginPermissions
   install?: {
     check: string
     steps: string[]