v0.21.3

vercel-labs/agent-browserv0.21.3Mar 20, 2026by github-actions[bot]

AI Summary

Patch release enhances connection stability for remote browsers and adds performance optimizations for snapshot comparisons.

Key Highlights

Added WebSocket Ping frames and TCP 'SO_KEEPALIVE' to prevent silent connection drops.
Fixed XPath selector support to correctly handle the 'xpath=' prefix.
Implemented a fast-path for identical snapshots to avoid unnecessary computation.

New Features

WebSocket keepalive for remote browsers
XPath selector support

Full Release Notes

### Patch Changes

-   6daad22: ### Bug Fixes

    -   **WebSocket keepalive for remote browsers** - Added WebSocket Ping frames and TCP `SO_KEEPALIVE` to prevent CDP connections from being silently dropped by intermediate proxies (reverse proxies, load balancers, service meshes) during idle periods (#936)
    -   **XPath selector support** - Fixed element resolution to correctly handle the `xpath=` selector prefix (#908)

    ### Performance

    -   **Fast-path for identical snapshots** - Short-circuits the Myers diff algorithm when comparing a snapshot to itself, avoiding unnecessary computation in retry and loop workloads where repeated identical snapshots are common (#922)

    ### Documentation

    -   Migrated page metadata from MDX files to `layout.tsx` (#904)
    -   Added search functionality and color improvements to docs (#927)
    -   Fixed desktop browser list in the iOS comparison table (#926)
    -   Created a new `providers/` section with dedicated provider pages (#928)