WP Manifestindependent plugin directory
manifest / performance / pb-cache-warmer

Page Builder Cache Guard

WordPress plugin that prevents missing CSS on page-builder sites (Divi, Elementor, Beaver Builder, Bricks, Oxygen) by warming origin cache after purge events and syncing Cloudflare's edge via API.

by Alex van Rossum / MipYip · github.com/avanrossum/pb-cache-warmer · website

★ 1stars

Install

Download source zip No release zip yet

This is the repository archive. It installs, but the folder name will carry the branch suffix and updates will not flow.

Install straight from GitHub with WP-CLI:

wp plugin install https://github.com/avanrossum/pb-cache-warmer/archive/refs/heads/main.zip
Updates itself. It ships its own updater (Plugin Update Checker), so new versions appear under Dashboard → Updates.
Readme github.com/avanrossum/pb-cache-warmer ↗

Prevents the "white page after cache purge" problem on WordPress sites using page builders.

If you run Divi, Elementor, Beaver Builder, Bricks, or Oxygen behind a server-side page cache and/or Cloudflare, you've seen it: a cache purge happens, and the next visitor gets an unstyled page. The CSS files that page builders generate on first render haven't been regenerated yet, and the cached HTML is pointing at files that don't exist.

Page Builder Cache Guard fixes this with a three-phase approach: force-regenerate CSS on origin, purge stale server cache entries, and sync Cloudflare's edge via API. A client-side health check catches anything that slips through.

Settings — Schedule, post types, and warmup configuration Settings — Cloudflare integration, health check, and run history

The Problem

Page builders (Divi, Elementor, Beaver Builder, etc.) generate per-post CSS files on first render and cache them on disk. When a cache purge happens, three failure modes can break your site:

Failure Mode What Happens
Origin Cold Start Page cache purged, next visitor triggers PHP render. Page builder writes CSS during render — everyone who arrived before the file was written gets a 404 on the stylesheet.
Cloudflare Stale HTML Cloudflare serves cached HTML referencing CSS files that no longer exist at origin. Browser requests CSS, CF fetches from origin, gets 404.
Page Cache / CSS Desync Server page cache serves HTML from before the most recent CSS regeneration. HTML references old filenames.

How It Works

Phase 1 — Origin Warmup

After any cache purge event (or on a schedule, or manually), the plugin crawls every published page with a cache-bypassing query string. This forces a full PHP render, which makes the page builder write all CSS files to disk. Randomized bypass tokens ensure CDN edges also treat each request as uncached.

Phase 1b — Server Page Cache Purge

When the client-side health check detects a broken page and triggers a heal, the plugin also purges the server-side page cache entry for that URL. Supports nginx-helper (FastCGI/Redis), WP Rocket, LiteSpeed Cache, W3 Total Cache, WP Super Cache.

Phase 2 — Cloudflare Cache Purge (Optional)

Calls Cloudflare's Cache Purge API to drop cached HTML and page-builder CSS. Only targets dynamic CSS paths (et-cache, Elementor, Beaver Builder, Bricks, Oxygen, Kadence) — stable WordPress assets are left alone.

Client-Side Health Check (Optional)

~600 bytes of inline JavaScript. Checks if every stylesheet loaded after page load. If any returns 404, calls the heal endpoint (Phase 1 + 1b + 2 for that URL), then reloads. Session storage guard prevents loops.

Supported Page Builders

  • Divi 4 (et-cache)
  • Elementor (/elementor/css/)
  • Beaver Builder (bb-plugin/cache)
  • Bricks
  • Oxygen
  • Kadence Blocks
  • GeneratePress

Supported Cache Plugins

Auto-triggers warmup on cache clear from: WP Rocket, LiteSpeed Cache, W3 Total Cache, WP Super Cache, Autoptimize, GridPane nginx-helper, Elementor, Beaver Builder, Bricks.

Installation

  1. Download the latest release from Releases
  2. Upload to /wp-content/plugins/
  3. Activate in WordPress admin
  4. Go to Settings → Cache Warmer
  5. Configure post types, schedule, and delay
  6. (Optional) Add Cloudflare API token for Phase 2
  7. (Optional) Enable client-side CSS health check
  8. Click "Run Warmup" to warm immediately

Auto-updates via GitHub releases are built in.

Cloudflare API Token

Create a token at dash.cloudflare.com/profile/api-tokens:

Permission Scope Required For
Zone — Cache Purge — Purge Your zone Phase 2 cache purge
Zone — Cache Settings — Edit Your zone Cache Rules management (optional)
Zone — Zone — Read Your zone Zone ID auto-detection (optional)

Advanced: Bypass Cloudflare for Phase 1

On CF-proxied servers, Phase 1 warmup traffic passes through Cloudflare unnecessarily. Send it directly to origin:

add_filter( 'pbcw_origin_base', fn() => 'http://127.0.0.1' );

Filters & Actions

Hook Type Purpose
pbcw_origin_base Filter Override base URL for Phase 1 requests
pbcw_post_types Filter Add/remove post types from warmup
pbcw_sslverify Filter SSL verification toggle
pbcw_dynamic_css_paths Filter Define which CSS paths are page-builder-generated
pbcw_purge_page_cache Action Custom page cache purge integration

Requirements

  • WordPress 6.0+
  • PHP 8.0+
  • Tested up to WordPress 6.8

License

GPL-2.0-or-later

Built by Alex van Rossum at MipYip. Read the deep dive on why page builder sites break after cache purges. More tools at mipyip.com/lab.