Caching content with query string parameters Varnish hashes the URL and uses this value as its cache key. When a single value in the URL changes, the cache key changes. This would result in a cache miss. Query string parameters are exceptionally prone to this: omitting a parameter, adding a parameter, or changing the order … Read more
Site using static homepage, redirects (301) and removes pluses from query string
REST API: Search products only in the names
When handling form submissions, it would generally be advisable to POST your form to a custom AJAX handler or wp-admin/admin-post.php form handler. If an external API integration requires you to accept the name parameter, setting up this functionality as a REST API endpoint or controller would give you fairly complete control over the query vars. … Read more
Query String Filtering API
I literally just ran into the same problem. I found the answer on another post: https://stackoverflow.com/questions/12682952/proper-url-forming-with-a-query-string-and-an-anchor-hashtag/48728926#48728926 Use <form> instead of <a>
Change admin_title of a plugin using code snippet/functions
Taxonomy archive uses incorrect template when query strings are used
Add rewrite rule to make Woocommerce product category page seo friendly
Hmm…i might be getting you wrong, but do you know that WP comes with an AJAX callback framework that helps you with this, making calling your own callback file unneccessary?