LiteSpeed Cache causes WooCommerce AJAX filters (WOPB/WooStore) to break over time

[ordient]

Hi,
I’m experiencing a recurring issue with LiteSpeed Cache and WooCommerce product filters across multiple sites.
Setup:

• WooCommerce
• LiteSpeed Cache plugin
• Using WOPB / WooStore for AJAX-based product filters

Issue:
The product filters (attributes like pa_*, price filters, etc.) stop working correctly after some time (typically after a few days).

• Filters work perfectly immediately after purging cache
• After some time, they become inconsistent or stop working
• Logging in (bypassing cache) makes everything work correctly again

This behavior is consistent across multiple sites with the same setup.
Testing performed:

• Added query strings to “Do Not Cache Query Strings” (pa_*, min_price, max_price, orderby) → no consistent fix
• Tested excluding a specific category from cache:
  I excluded /product-category/felgur/ from cache while keeping /product-category/dekk/ cached.
  • Filters on the non-cached category (felgur) always work correctly
  • Filters on the cached category (dekk) eventually break

→ This consistently confirms the issue is directly related to LiteSpeed page caching.
Hosting confirmation:
Hostinger confirmed:

• No server-level cache is active
• No additional page caching outside LiteSpeed

Conclusion so far:
It appears that cached category pages become stale or inconsistent over time, which conflicts with WOPB’s AJAX filtering.
Questions:

1. What is the recommended way to handle AJAX-based filters (like WOPB/WowStore) with LiteSpeed Cache?
2. Should WooCommerce category pages be excluded from cache entirely in this case?
3. Is there a way to prevent stale cached HTML from breaking filter functionality (e.g., ESI, TTL tuning, or specific exclusions)?
4. Is this a known limitation when using third-party AJAX filter plugins?

I would prefer to keep caching enabled for performance, but need a stable and reliable solution for filters.
Thanks in advance.