browser dblclick is not supported by this browser backend

Error message

browser dblclick is not supported by this browser backend

What it means

The `browser dblclick` command checks `typeof page.dblClick === 'function'` before running; backends without double-click support throw this capability error. It prevents a TypeError and gives a clear message that the backend cannot perform double-clicks.

Source

Thrown at src/cli.ts:2147

      if (!resolvedTarget) return;
      const parsed = nthToResolveOpts(opts?.nth);
      if ('error' in parsed) {
        console.log(JSON.stringify({ error: { code: 'usage_error', message: parsed.error } }, null, 2));
        process.exitCode = EXIT_CODES.USAGE_ERROR;
        return;
      }
      const { focused, matches_n, match_level } = await page.focus(resolvedTarget, parsed.opts);
      console.log(JSON.stringify({ focused, target: resolvedTarget, matches_n, match_level }, null, 2));
    }));

  addBrowserTabOption(
    addSemanticLocatorOptions(browser.command('dblclick'))
      .argument('[target]', 'Numeric ref (from browser state / find), CSS selector, or omit when using --role/--name/etc.')
      .option('--nth <n>', 'When <target> is a multi-match CSS selector, pick the nth match (0-based)')
      .description('Double-click element — JSON envelope {dblclicked, target, matches_n}'),
  )
    .action(browserAction(async (page, target, opts) => {
      if (typeof page.dblClick !== 'function') throw new Error('browser dblclick is not supported by this browser backend');
      const resolvedTarget = await resolveWriteTargetOrPrint(page, target, opts ?? {});
      if (!resolvedTarget) return;
      const parsed = nthToResolveOpts(opts?.nth);
      if ('error' in parsed) {
        console.log(JSON.stringify({ error: { code: 'usage_error', message: parsed.error } }, null, 2));
        process.exitCode = EXIT_CODES.USAGE_ERROR;
        return;
      }
      const { matches_n, match_level } = await page.dblClick(resolvedTarget, parsed.opts);
      console.log(JSON.stringify({ dblclicked: true, target: resolvedTarget, matches_n, match_level }, null, 2));
    }));

  const runCheckCommand = async (
    page: Awaited<ReturnType<typeof getBrowserPage>>,
    target: unknown,
    opts: Record<string, unknown>,
    checked: boolean,
  ): Promise<void> => {

View on GitHub (pinned to 49907e53dc)

Solutions

Use a full-featured backend (Playwright/Puppeteer) that implements dblClick.
Emulate with `browser eval` dispatching two click events or a dblclick event.
Update the backend adapter/driver to a version supporting dblClick.

Example fix

// before
browser --backend minimal dblclick '.row'
// after
browser --backend playwright dblclick '.row'

Defensive patterns

Strategy: type-guard

Validate before calling

const page = await getBrowserPage();
if (typeof page.dblClick !== 'function') {
  throw new Error('Current backend cannot double-click');
}

Type guard

function supportsDblClick(page) {
  return typeof page?.dblClick === 'function';
}

Try / catch

try {
  await run(['browser', 'dblclick', sel]);
} catch (err) {
  if (String(err.message).includes('dblclick is not supported')) {
    await run(['browser', 'eval', `const el=document.querySelector('${sel}'); el.dispatchEvent(new MouseEvent('dblclick',{bubbles:true}))`]);
  } else throw err;
}

Prevention

Feature-detect dblClick before use.
Avoid minimal drivers for interaction-heavy scripts.
Centralize backend capability checks in one helper.
Test scripts against the target backend in CI.

When it happens

Trigger: Running `browser dblclick [target]` on a browser backend that does not implement `page.dblClick`.

Common situations: Using lightweight or custom browser drivers that only expose click/evaluate; older backend versions predating dblClick support in the adapter.

Related errors

AI-assisted analysis of jackwener/OpenCLI@49907e53dc (2026-08-29). Data as JSON: /api/errors/d51084320a603d2e. Report an issue: GitHub.