fix(desktop): open links clicked in the integrated terminal

Both of xterm's link paths activate through `window.open()`, which the
window's setWindowOpenHandler denies, so ⌘-clicking a URL did nothing but
log "Opening link blocked as opener could not be cleared" — and the OSC 8
path fronted that dead end with a raw confirm() dialog. Route both through
the desktop bridge, the path every other external link in the app takes.

⌘-click on macOS, Ctrl-click elsewhere, matching VS Code's integrated
terminal, Terminal.app, and iTerm2. A bare click stays with the selection so
a misclick on a URL can't launch a browser.

apps/desktop/src/app/right-sidebar/terminal/links.test.ts

@@ -0,0 +1,75 @@
+import type { ILink, Terminal as TerminalType } from '@xterm/xterm'
+import { Terminal } from '@xterm/xterm'
+import { beforeEach, describe, expect, it, vi } from 'vitest'
+
+import { isTerminalLinkActivation, terminalLinkHandler, terminalWebLinksAddon } from './links'
+
+const openExternal = vi.fn()
+const click = (init: Partial<MouseEvent> = {}) => ({ ctrlKey: false, metaKey: false, ...init })
+
+beforeEach(() => {
+  openExternal.mockClear()
+  Object.defineProperty(window, 'hermesDesktop', { configurable: true, value: { openExternal } })
+  // jsdom reports a non-mac platform, so the activation modifier resolves to
+  // Ctrl unless we say otherwise.
+  Object.defineProperty(navigator, 'platform', { configurable: true, value: 'MacIntel' })
+})
+
+// Drive the addon the way xterm does: load it on a real terminal, write a URL
+// into the buffer, then activate the link its provider reports.
+async function clickLinkIn(text: string, event: MouseEvent) {
+  const term = new Terminal({ allowProposedApi: true, cols: 80, rows: 10 })
+  const providers: Array<Parameters<TerminalType['registerLinkProvider']>[0]> = []
+  const register = term.registerLinkProvider.bind(term)
+
+  term.registerLinkProvider = provider => {
+    providers.push(provider)
+
+    return register(provider)
+  }
+
+  term.loadAddon(terminalWebLinksAddon())
+
+  await new Promise<void>(resolve => term.write(`${text}\r\n`, resolve))
+
+  const links = await new Promise<ILink[]>(resolve => providers[0].provideLinks(1, found => resolve(found ?? [])))
+
+  links[0]?.activate(event, links[0].text)
+
+  return links[0]?.text
+}
+
+describe('terminal links', () => {
+  it('opens a ⌘-clicked URL through the desktop bridge, not the window.open Electron denies', async () => {
+    const uri = 'https://example.com/path'
+
+    expect(await clickLinkIn(uri, new MouseEvent('click', { metaKey: true }))).toBe(uri)
+    expect(openExternal).toHaveBeenCalledWith(uri)
+  })
+
+  it('leaves a bare click to the selection, so a misclick never launches a browser', async () => {
+    await clickLinkIn('https://example.com/path', new MouseEvent('click'))
+
+    expect(openExternal).not.toHaveBeenCalled()
+  })
+
+  it('routes OSC 8 hyperlinks the same way, instead of xterm\u2019s confirm() dialog', () => {
+    terminalLinkHandler.activate(new MouseEvent('click', { metaKey: true }), 'https://example.com/osc8', {
+      end: { x: 10, y: 1 },
+      start: { x: 1, y: 1 }
+    })
+
+    expect(openExternal).toHaveBeenCalledWith('https://example.com/osc8')
+  })
+})
+
+describe('isTerminalLinkActivation', () => {
+  it('takes the platform modifier: ⌘ on macOS, Ctrl elsewhere', () => {
+    expect(isTerminalLinkActivation(click({ metaKey: true }), true)).toBe(true)
+    expect(isTerminalLinkActivation(click({ ctrlKey: true }), false)).toBe(true)
+  })
+
+  it('keeps Ctrl+click free on macOS, where the OS reads it as a right-click', () => {
+    expect(isTerminalLinkActivation(click({ ctrlKey: true }), true)).toBe(false)
+  })
+})

apps/desktop/src/app/right-sidebar/terminal/links.ts

@@ -0,0 +1,35 @@
+import { WebLinksAddon } from '@xterm/addon-web-links'
+import type { ILinkHandler } from '@xterm/xterm'
+
+import { openExternalLink } from '@/lib/external-link'
+
+import { isMacPlatform } from './selection'
+
+// Both of xterm's link paths — the web-links addon (URLs it finds in the
+// buffer) and the core OSC 8 provider (hyperlinks a CLI emits explicitly) —
+// activate through `window.open()`, which the window's setWindowOpenHandler
+// denies: a click did nothing but log "Opening link blocked as opener could not
+// be cleared", and OSC 8 fronted that dead end with a raw confirm() dialog.
+// Route both through the desktop bridge, the path every other external link in
+// the app takes.
+//
+// ⌘-click on macOS, Ctrl-click elsewhere — VS Code's integrated terminal,
+// Terminal.app, and iTerm2 all agree. A bare click belongs to the selection, so
+// a misclick on a URL can't launch a browser mid-sentence. ⌥ stays out of it:
+// that's the force-selection drag over mouse-mode TUIs.
+export function isTerminalLinkActivation(
+  event: Pick<MouseEvent, 'ctrlKey' | 'metaKey'>,
+  isMac = isMacPlatform()
+): boolean {
+  return isMac ? event.metaKey : event.ctrlKey
+}
+
+const activate = (event: MouseEvent, uri: string) => {
+  if (isTerminalLinkActivation(event)) {
+    openExternalLink(uri)
+  }
+}
+
+export const terminalLinkHandler: ILinkHandler = { activate }
+
+export const terminalWebLinksAddon = () => new WebLinksAddon(activate)

apps/desktop/src/app/right-sidebar/terminal/use-agent-terminal.ts

@@ -1,6 +1,5 @@
 import { FitAddon } from '@xterm/addon-fit'
 import { Unicode11Addon } from '@xterm/addon-unicode11'
-import { WebLinksAddon } from '@xterm/addon-web-links'
 import { WebglAddon } from '@xterm/addon-webgl'
 import { Terminal } from '@xterm/xterm'
 import { useEffect, useRef } from 'react'
@@ -12,6 +11,7 @@ import { useTheme } from '@/themes/context'
 import { registerAgentTerminalWriter } from './agent-terminal-stream'
 import { makeTerminalReader, registerTerminalReader } from './buffer'
 import { mirrorSelection, terminalClipboardIntent } from './clipboard'
+import { terminalLinkHandler, terminalWebLinksAddon } from './links'
 import { isMacPlatform, resolveSurfaceColor, terminalTheme } from './selection'
 
 // Read-only terminal for an agent background process: a write-only xterm (no PTY,
@@ -51,6 +51,7 @@ export function useAgentTerminal({ active, id, procId }: { active: boolean; id:
       fontWeightBold: 'bold',
       letterSpacing: 0,
       lineHeight: 1.12,
+      linkHandler: terminalLinkHandler,
       minimumContrastRatio: 4.5,
       scrollback: 1000,
       theme: surfaceTheme()
@@ -59,7 +60,7 @@ export function useAgentTerminal({ active, id, procId }: { active: boolean; id:
     const fit = new FitAddon()
     term.loadAddon(fit)
     term.loadAddon(new Unicode11Addon())
-    term.loadAddon(new WebLinksAddon())
+    term.loadAddon(terminalWebLinksAddon())
     term.unicode.activeVersion = '11'
     term.open(host)
     termRef.current = term

apps/desktop/src/app/right-sidebar/terminal/use-terminal-session.ts

@@ -1,7 +1,6 @@
 import { FitAddon } from '@xterm/addon-fit'
 import { SerializeAddon } from '@xterm/addon-serialize'
 import { Unicode11Addon } from '@xterm/addon-unicode11'
-import { WebLinksAddon } from '@xterm/addon-web-links'
 import { WebglAddon } from '@xterm/addon-webgl'
 import { Terminal } from '@xterm/xterm'
 import { useCallback, useEffect, useMemo, useRef, useState } from 'react'
@@ -16,6 +15,7 @@ import { $terminalInjection } from '../store'
 
 import { makeTerminalReader, registerTerminalReader } from './buffer'
 import { mirrorSelection, terminalClipboardIntent } from './clipboard'
+import { terminalLinkHandler, terminalWebLinksAddon } from './links'
 import {
   isAddSelectionShortcut,
   isMacPlatform,
@@ -514,6 +514,10 @@ export function useTerminalSession({
       fontWeightBold: 'bold',
       letterSpacing: 0,
       lineHeight: 1.12,
+      // OSC 8 hyperlinks (gh, cargo, npm, ls --hyperlink) activate through this
+      // handler; without it xterm shows a raw confirm() and then a window.open
+      // Electron denies.
+      linkHandler: terminalLinkHandler,
       // Full-screen TUIs (hermes --tui, vim) grab the mouse, so a plain drag
       // can't select — ⌥-drag (macOS) / Shift-drag (else) forces a native
       // selection over mouse-mode apps, which ⌘/Ctrl+L then sends to chat.
@@ -536,7 +540,7 @@ export function useTerminalSession({
     term.loadAddon(fit)
     term.loadAddon(serialize)
     term.loadAddon(new Unicode11Addon())
-    term.loadAddon(new WebLinksAddon())
+    term.loadAddon(terminalWebLinksAddon())
     term.unicode.activeVersion = '11'
 
     // Replay last session's scrollback before the fresh shell boots. The process