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Major Update: Ninja Forms Integration + Cookie Engine Rewrite

ninja forms support duplicate killer integration

What’s new in 1.4.7

  • ✅ New: Full Ninja Forms support
    Duplicate Killer now integrates seamlessly with Ninja Forms, allowing you to block duplicate submissions at the data level, before entries are saved or actions are triggered.
  • 🔁 Cookie Engine Completely Rewritten
    The cookie handling system has been fully redesigned for improved reliability, performance, and compatibility.
    The new engine:
    • Uses a modern, external JavaScript approach (no inline scripts)
    • Is fully compatible with strict Content Security Policies (CSP)
    • Works correctly with cache plugins such as LiteSpeed
    • Detects supported form plugins dynamically in the DOM
    • Sets cookies only when a form is actually present on the page
  • 🛡️ Improved Uniqueness Detection Logic
    Cookie-based uniqueness is now applied only when explicitly enabled for a specific form (FREE or PRO), ensuring correct behavior even when multiple forms with different settings are present on the same page.
  • ⚡ Performance Optimizations
    The new architecture introduces early-exit logic and minimal runtime overhead, resulting in near-zero impact on pages without forms and faster execution overall.
  • 🧩 Extensible Architecture (Future-Ready)
    The new cookie engine was built with extensibility in mind, making it easy to add support for additional form plugins such as Elementor Forms, Forminator, and WPForms in upcoming releases.

Why this matters

This update significantly improves how Duplicate Killer handles user identification and duplicate prevention, especially on modern WordPress setups that use aggressive caching, security headers, or multiple form plugins. The result is cleaner data, fewer false positives, and rock-solid compatibility.

Check free version right now!

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