JPKCom Post Filter

Plugin Name: JPKCom Post Filter
Plugin URI: https://github.com/JPKCom/jpkcom-post-filter
Description: Faceted navigation and filtering of Posts, Pages, and Custom Post Types via WordPress taxonomies — SEO-friendly URLs, AJAX updates, and full screen reader support.
Version: 1.4.4
Author: Jean Pierre Kolb jpk@jpkc.com
Author URI: https://www.jpkc.com/
Contributors: JPKCom
Tags: filter, taxonomy, faceted search, custom post type, AJAX
Requires at least: 7.0
Tested up to: 7.1
Requires PHP: 8.3
Stable tag: 1.4.4
License: GPL-2.0-or-later
License URI: https://www.gnu.org/licenses/gpl-2.0.html
Text Domain: jpkcom-post-filter
Domain Path: /languages

Filter any post type by taxonomy terms — SEO-friendly URLs, AJAX, and shortcodes included.

---

Description

JPKCom Post Filter adds faceted taxonomy filtering to any WordPress archive page or via shortcodes. Visitors can narrow down posts, pages, or custom post types by one or more taxonomy terms, with every filter state reflected in the URL for bookmarking and sharing.

Key Features

• SEO-friendly URL schema — Filter state encoded in the URL path: /blog/filter/category1+category2/tag1/
• Four filter layouts — Horizontal bar, columns, sidebar, or dropdown with active-count badge
• Three list layouts — Cards (grid), rows (list), or minimal (compact)
• Hybrid rendering — Server-side on first load; AJAX + history.pushState when JS is available; full page reload fallback when JS is disabled
• Auto-inject mode — Automatically wraps theme archive loops with filter UI (no shortcode needed)
• Shortcode mode — Place filter, list, and pagination on archive pages via shortcodes
• Gutenberg Blocks — Three native blocks (Post Filter, Post List, Post Pagination) with live editor preview and full InspectorControls panel
• Elementor Widgets — Three widgets (Post Filter, Post List, Post Pagination) in a dedicated widget category, loaded only when Elementor is active
• Oxygen Builder Elements — Three elements (Post Filter, Post List, Post Pagination) in a custom toolbar section, loaded only when Oxygen Builder Classic is active
• Custom taxonomy creation — Register new WordPress taxonomies directly from the Filter Groups admin page
• Plus/Minus interaction mode — Additive (+ icon) or exclusive (label click) filter selection
• Show More button — Collapse long filter lists behind a configurable threshold
• Four color schemes — Default, Dark, Contrast, Monochrome (all overridable)
• Three stylesheet modes — Full plugin CSS, CSS variables only, or fully disabled
• Four-layer caching — Object cache, transients, APCu, and PHP file cache for settings
• Full accessibility — aria-live regions, aria-pressed toggle buttons, screen-reader-only counts
• Multi-language — Ships with EN, de_DE, and de_DE_formal translations
• No dependencies — No ACF, no Bootstrap, no jQuery required

---

Installation

1. Upload the jpkcom-post-filter directory to /wp-content/plugins/.
2. Activate the plugin via Plugins → Installed Plugins.
3. Go to Post Filter → General and select the post types to filter.
4. Go to Post Filter → Filter Groups and add the taxonomies you want as filter dimensions.
5. Go to Settings → Permalinks and click Save Changes to flush rewrite rules.

---

Configuration

General Settings

Option	Description
Enabled Post Types	Which post types to activate filtering for
Auto-Inject Filter	Automatically add filter UI to archive/blog pages per post type
URL Endpoint	URL path segment for filter URLs (default: filter)
Bare Endpoint Behaviour	What happens when /filter/ is accessed without filter terms: 404, redirect to blog homepage, or custom URL
Max Filter Combinations	Maximum simultaneous active filter groups (affects URL and JS)
Max. Filters per Group	Maximum terms selectable within one filter group (0 = unlimited)
Debug Mode	Use debug-templates/ and write detailed logs to PHP error log

After changing the URL endpoint go to Settings → Permalinks and click Save, or use the Flush Rewrite Rules button on the General page.

Filter Groups

Each filter group maps a taxonomy to a URL position. Groups are applied in the configured order:

/archive-base/filter/{group-1-slugs}/{group-2-slugs}/
/blog/filter/web-design+marketing/wordpress/

Configure groups at Post Filter → Filter Groups. Each group has:

Field	Description
Taxonomy	Select an existing WP taxonomy, or enable "Register as new taxonomy" to create one
Label	Displayed in the filter bar (and as admin label for new taxonomies)
Post Types	Which archive pages this group appears on (empty = all enabled post types)
Order	Numeric sort position — determines URL segment order
Enabled	Toggle group on/off without deleting it

Creating new taxonomies — When "Register as new WordPress taxonomy" is checked, additional fields appear:

Field	Description
Taxonomy Slug	Unique identifier, lowercase letters and hyphens
Rewrite Slug	URL prefix for term archive pages
Hierarchical	Category-like (parent/child) or tag-like (flat)
Public	Enable frontend term archive pages
Admin Column	Show taxonomy as column in post list table
REST API	Expose in REST API (required for Gutenberg)

Warning: Removing a filter group that registered a custom taxonomy will unregister that taxonomy and all term assignments on posts will be permanently lost.

Layout & Design

Post Filter → Layout & Design contains six tabs:

Tab: Global — Default filter layout (bar / columns / sidebar / dropdown), default list layout (cards / rows / minimal), and global spacing/typography variables.

Tab: Filter — Colors and dimensions for filter buttons (default, hover, active state), the reset button, and dropdown panel styling.

Tab: Posts — Card background, border, shadow, radius, padding; grid column counts for desktop, tablet, and mobile; typography and link colors.

Tab: Pagination — Colors for pagination buttons (default, hover, active), border radius, and font size.

Tab: Color Schemes — Choose a preset color scheme. Custom variable overrides from the other tabs are applied on top.

Scheme	Description
Default	WordPress blue accent, light backgrounds
Dark	Dark backgrounds, light text, blue accent
Contrast	Red reset button for stronger visual differentiation
Monochrome	Black, white, and grey only — no color accent

Tab: Advanced — Stylesheet mode, filter interaction, pagination position, and custom CSS.

Setting	Options	Description
Stylesheet Mode	Full / Variables only / Disabled	Full loads the complete plugin CSS; Variables only outputs only the :root block as inline style; Disabled loads nothing
Reset Button Visibility	Always / On selection / Never	Controls when the "Reset filters" link is shown
Plus/Minus Mode	on/off	Adds +/– icons; clicking the label selects a filter exclusively, clicking + adds it to the current selection
Show More Button	on/off + threshold	Hides filters beyond the threshold behind a … toggle (not available in Dropdown layout)
Pagination Position	Below / Above / Both	Auto-inject only; shortcode pagination is placed manually
Custom CSS	textarea	Additional rules appended after the plugin stylesheet

Cache & Performance

Enable or disable individual cache layers, set the transient TTL, and clear caches from Post Filter → Cache.

Layer	Description
Object Cache	wp_cache_* for query results; invalidated on save_post / deleted_post
Transient Cache	get/set_transient for taxonomy term lists; invalidated on term changes
Settings File Cache	PHP include cache in .ht.jpkcom-post-filter-settings/; fastest for settings reads

Cache TTL applies to transients. Object cache respects the TTL of the active object cache backend.

Import / Export

All plugin settings (general, layout, cache, filter_groups) can be exported as a JSON file and re-imported at Post Filter → Import / Export. Useful for migrating settings between environments.

---

Shortcodes

Important: Where shortcodes work

Shortcodes always connect to the WordPress archive of the configured post type. When a filter is activated the browser navigates to a URL like /news/filter/slug/ — the base URL is always the post type archive, not the page the shortcode is placed on.

Supported placements:

1. Archive template — Embed shortcodes inside an archive template via a page builder or the Gutenberg Full Site Editor. The page IS the archive, so archive URL = current URL.
2. Posts Page (post type only) — Assign a WordPress page as the "Posts Page" under Settings → Reading. WordPress treats that page as the blog archive, so /blog/ and the shortcode page are the same URL.
3. Auto-inject instead — Enable General → Auto-Inject Filter to have the plugin inject the filter UI into archive pages automatically, without any shortcode.

What does not work: Placing shortcodes on an arbitrary custom page (e.g. /test/) whose URL has nothing to do with the post type archive. Filter clicks, AJAX results, and pagination will all redirect to the archive URL, leaving the custom page behind.

---

[jpkcom_postfilter_filter]

Renders the filter bar.

Attribute	Values	Default
post_type	any registered post type	post
layout	bar / columns / sidebar / dropdown	backend setting
groups	comma-separated group slugs	all groups
reset	true / false / always	backend setting
class	string	—

The reset attribute overrides the global Reset Button Visibility setting: false forces "never", always forces "always", true uses the backend setting.

[jpkcom_postfilter_list]

Renders the filtered post list.

Attribute	Values	Default
post_type	any registered post type	post
layout	cards / rows / minimal	backend setting
limit	integer	-1 (all)
orderby	date / title / menu_order	date
order	ASC / DESC	DESC
class	string	—

[jpkcom_postfilter_pagination]

Renders pagination for the filtered list. Must be placed after [jpkcom_postfilter_list]. Returns empty output when there is only one page.

Attribute	Values	Default
post_type	any registered post type	post
class	string	—

Example

[jpkcom_postfilter_filter post_type="portfolio" layout="dropdown"]
[jpkcom_postfilter_list post_type="portfolio" layout="cards" limit="12"]
[jpkcom_postfilter_pagination post_type="portfolio"]

Use the interactive shortcode builder at Post Filter → Shortcodes to generate snippets without writing code.

---

Gutenberg Blocks

Three native Gutenberg blocks are available under the JPKCom Post Filter block category. They work in the classic Block Editor and in the Full Site Editor (FSE).

Post Filter

Renders the filter/facets UI.

Setting	Options	Default
Post Type	any registered post type	post
Layout	Bar / Sidebar / Dropdown / Columns	backend setting
Filter Groups	comma-separated slugs	all groups
Reset Button	Default / Always / Never	backend setting

Post List

Renders the filtered post listing.

Setting	Options	Default
Post Type	any registered post type	post
Layout	Cards / Rows / Minimal / Theme	backend setting
Posts per Page	-1 to 100	5
Order By	Date / Title / Menu Order	date
Order	ASC / DESC	DESC

Post Pagination

Renders pagination for the post listing. Can be placed both above and below the Post List block — the plugin pre-scans the block tree before rendering to ensure pagination works at any position. Shows a static preview with example pages in the editor.

Setting	Options	Default
Post Type	any registered post type	post

Block placement notes

• All three blocks must use the same Post Type setting to be paired correctly.
• The filter bar and results zone are paired via data-jpkpf-post-type attributes — AJAX filtering works across blocks on the same page.
• Pagination blocks placed above the Post List block work correctly: the plugin pre-runs the list query before any block renders.
• In the editor, blocks show a live server-side preview. JS-driven features (Show More, Plus/Minus) are replicated server-side for accurate previews.

Building from source

Block editor scripts require a build step:

npm install
npm run build

Built files are output to blocks/build/. The plugin skips block registration when the build directory is missing.

---

Elementor Widgets

Three Elementor widgets are available under the JPKCom Post Filter widget category. They are only loaded when Elementor is active.

Post Filter

Control	Type	Default
Post Type	Select	post
Layout	Select (Default / Bar / Sidebar / Dropdown / Columns)	backend setting
Filter Groups	Text (comma-separated slugs)	all groups
Reset Button	Select (Default / Always / Never)	backend setting
CSS Class	Text	—

Post List

Control	Type	Default
Post Type	Select	post
Layout	Select (Default / Cards / Rows / Minimal / Theme)	backend setting
Posts per Page	Number (-1 to 100)	5
Order By	Select (Date / Title / Menu Order / Modified / Random)	date
Order	Select (DESC / ASC)	DESC
CSS Class	Text	—

Post Pagination

Control	Type	Default
Post Type	Select	post
CSS Class	Text	—

Widget placement notes

• All three widgets must use the same Post Type to work together.
• Widgets call the same shortcode functions as the Gutenberg blocks — AJAX filtering, SEO-friendly URLs, and pagination work identically.
• The Pagination widget can be placed both above and below the Post List widget.
• Elementor templates for archive pages are the recommended placement.

---

Oxygen Builder Elements

Three Oxygen Builder Classic (v3.x+) elements are available under the Post Filter section in the Oxygen Add Elements panel. They are only loaded when Oxygen Builder is active.

Post Filter

Control	Type	Default
Post Type	Dropdown	post
Layout	Dropdown (Default / Bar / Sidebar / Dropdown / Columns)	backend setting
Filter Groups	Text (comma-separated slugs)	all groups
Reset Button	Dropdown (Default / Always / Never)	backend setting

Post List

Control	Type	Default
Post Type	Dropdown	post
Layout	Dropdown (Default / Cards / Rows / Minimal / Theme)	backend setting
Posts per Page	Text (-1 = all)	5
Order By	Dropdown (Date / Title / Menu Order / Modified / Random)	date
Order	Dropdown (Descending / Ascending)	DESC

Post Pagination

Control	Type	Default
Post Type	Dropdown	post

Element placement notes

• All three elements must use the same Post Type to work together.
• Elements call the same shortcode functions as the Gutenberg blocks and Elementor widgets — AJAX filtering, SEO-friendly URLs, and pagination work identically.
• The Pagination element can be placed both above and below the Post List element.
• Oxygen archive templates are the recommended placement. Auto-inject mode does not work with Oxygen since it bypasses the standard WordPress template system.
• Elements use the OxyEl API and appear in Oxygen's "Type to search components" field when searching for "post", "filter", "pagination", or "jpkcom".

---

Auto-Inject Mode

When Auto-Inject Filter is enabled for a post type in General Settings, the plugin automatically wraps the theme archive loop with the filter UI — no shortcode or template modification required. The filter bar is inserted before the loop and the results zone wraps the loop output.

The pagination position for auto-inject mode is configurable (Below / Above / Both) in Layout & Design → Advanced.

Auto-inject works by hooking into loop_start and loop_end on archive/blog pages. It does not run on singular posts, search results, or pages.

---

Template Overrides

Templates can be overridden per theme without editing plugin files. The loader checks these locations in order:

1. themes/{child-theme}/jpkcom-post-filter/{template}
2. themes/{parent-theme}/jpkcom-post-filter/{template}
3. mu-plugins/jpkcom-post-filter-overrides/templates/{template}
4. Plugin templates/ (or debug-templates/ when debug mode is on)

Example: To override the cards list template, copy plugins/jpkcom-post-filter/templates/partials/list/list-cards.php to themes/your-theme/jpkcom-post-filter/partials/list/list-cards.php.

Available templates

partials/filter/filter-bar.php       ← Horizontal bar layout
partials/filter/filter-columns.php   ← Columns layout
partials/filter/filter-sidebar.php   ← Sidebar layout
partials/filter/filter-dropdown.php  ← Dropdown layout
partials/list/list-cards.php         ← Cards (grid) layout
partials/list/list-rows.php          ← Rows layout
partials/list/list-minimal.php       ← Minimal (ul/li) layout
partials/pagination/pagination.php   ← Pagination
shortcodes/filter.php                ← Shortcode wrapper → delegates to partials/filter/
shortcodes/posts-list.php            ← Shortcode wrapper → delegates to partials/list/
shortcodes/pagination.php            ← Shortcode wrapper → delegates to partials/pagination/

Template action hooks

// Fires before and after every template part
add_action( 'jpkcom_postfilter_before_template_part', function( $path, $slug, $name, $args ) { ... }, 10, 4 );
add_action( 'jpkcom_postfilter_after_template_part',  function( $path, $slug, $name, $args ) { ... }, 10, 4 );

---

CSS Customisation

All styles use CSS custom properties prefixed --jpkpf-. Override them in your theme stylesheet, via the CSS Variables fields in Layout & Design, or via the Custom CSS field:

:root {
    --jpkpf-primary:             #0073aa;
    --jpkpf-primary-hover:       #005d8c;
    --jpkpf-filter-bg:           #f0f0f1;
    --jpkpf-filter-active-bg:    #0073aa;
    --jpkpf-filter-active-color: #ffffff;
    --jpkpf-filter-radius:       3px;
    --jpkpf-gap:                 0.5rem;
    --jpkpf-card-radius:         4px;
    --jpkpf-transition:          0.2s ease;
}

---

Abilities API

WordPress 6.9 introduced the Abilities API: a registry of machine-readable capabilities that AI assistants, MCP clients and automation tools can discover and call. This plugin registers two of them, both read-only, so an assistant can answer questions about your posts without scraping the front end.

Ability	What it does
jpkcom-post-filter/list-filters	Reports which taxonomies and terms a post type can be filtered by, with a post count per term
jpkcom-post-filter/query-posts	Runs a filtered, paginated query and returns the matching posts plus a shareable filter URL

The point of the pair is that the first one removes the guesswork from the second: an assistant looks up the real taxonomy keys and term slugs, then filters with values that exist. A filter naming a taxonomy your site does not have is rejected with an error listing the valid ones — it never silently returns your whole archive instead.

What a call looks like

Both are reachable at /wp-json/wp-abilities/v1/. Because they only read, they answer on GET:

GET /wp-json/wp-abilities/v1/abilities/jpkcom-post-filter/list-filters/run?input[post_type]=post

{ "post_type": "post",
  "groups": [ { "taxonomy": "category", "label": "Kategorie",
                "terms": [ { "slug": "allgemein", "name": "Allgemein", "count": 2 }, … ] } ] }

GET /wp-json/wp-abilities/v1/abilities/jpkcom-post-filter/query-posts/run
      ?input[post_type]=post&input[filters][category][]=allgemein&input[per_page]=3

{ "post_type": "post", "filters": { "category": [ "allgemein" ] },
  "total": 2, "page": 1, "per_page": 3, "total_pages": 1,
  "filter_url": "https://example.com/filter/allgemein/",
  "unknown_terms": {},
  "posts": [ { "id": 143, "title": "…", "url": "…", "date": "…", "excerpt": "…",
               "terms": { "category": [ { "slug": "allgemein", "name": "Allgemein" } ] } } ] }

query-posts accepts post_type, filters, page, per_page (1–50) and search. Terms within one taxonomy are combined with OR, different taxonomies with AND — the same logic as the filter bar on your site. A term slug that matches nothing is not an error: the query runs and the slug is reported under unknown_terms, so the caller can tell a typo apart from an empty result.

filter_url comes back empty whenever no front-end address would show exactly the posts listed beside it — a post type without an archive page, a filter combination longer than your configured limits, a page after the first requested with a page size other than your site's own "posts per page", or a page past the last one. The results are complete either way; the assistant simply has no link to pass on.

What is exposed, and to whom

• Only published posts. The query cannot reach drafts, private or trashed content, and cannot be talked into it — the post status is fixed in the code, not a parameter.
• Only post types you have enabled for filtering, and only taxonomies you have configured as filter groups.
• Running an ability requires a logged-in user with the read capability. Listing the available abilities is likewise restricted to logged-in users — but note that any logged-in user, including a subscriber, can then see both abilities' descriptions and parameter schemas. That is how WordPress core gates every ability, not something specific to this plugin.

Turning it off, or tightening it

Add this to wp-config.php to register nothing at all:

define( 'JPKCOM_POSTFILTER_ABILITIES', false );

To keep the abilities but raise the bar for running them, filter the capability:

add_filter( 'jpkcom_postfilter_ability_capability', static fn(): string => 'edit_posts' );

To keep them out of MCP clients while leaving the REST route intact, or the other way round, use jpkcom_postfilter_ability_meta — see the Filters section below.

---

Developer Reference

See CLAUDE.md in the plugin root for the full developer reference including architecture decisions, constant definitions, cache layer documentation, template action hooks, and implementation notes.

Constants (wp-config.php overridable)

Constant	Default	Purpose
JPKCOM_POSTFILTER_VERSION	'1.0.0'	Plugin version
JPKCOM_POSTFILTER_DEBUG	WP_DEBUG	Enables debug mode and debug templates
JPKCOM_POSTFILTER_CACHE_ENABLED	true	Master cache toggle
JPKCOM_POSTFILTER_URL_ENDPOINT	'filter'	URL path segment
JPKCOM_POSTFILTER_SETTINGS_DIR	WP_CONTENT_DIR . '/.ht.jpkcom-post-filter-settings'	Settings file cache location
JPKCOM_POSTFILTER_MAX_FILTER_COMBOS	3	Default max filter group combinations
JPKCOM_POSTFILTER_ABILITIES	true	Registers the WordPress Abilities API integration. Set to false to withdraw both abilities from REST and MCP entirely.

JavaScript data attributes

<!-- Auto-inject mode: plugin adds data-jpkpf-wrapper automatically -->
<div data-jpkpf-wrapper data-jpkpf-base-url="/blog/">
    <nav data-jpkpf-filter-bar data-jpkpf-post-type="post">…</nav>
    <div data-jpkpf-results data-jpkpf-post-type="post" aria-live="polite">…</div>
</div>

<!-- Shortcode / Block / Elementor / Oxygen mode: paired by data-jpkpf-post-type -->
<nav data-jpkpf-filter-bar data-jpkpf-post-type="portfolio" data-jpkpf-base-url="/portfolio/">…</nav>
<div data-jpkpf-results data-jpkpf-post-type="portfolio">…</div>
<nav data-jpkpf-pagination data-jpkpf-post-type="portfolio">…</nav>

The data-jpkpf-pagination attribute on standalone pagination elements (blocks/shortcodes/Elementor) enables the JS to swap pagination content during AJAX filter requests, keeping pagination links filter-aware.

Key PHP functions

// Settings
jpkcom_postfilter_settings_get( 'general', 'url_endpoint', 'filter' )
jpkcom_postfilter_settings_get_group( 'layout' )
jpkcom_postfilter_settings_save( 'general', $data )
jpkcom_postfilter_settings_delete_cache( '*' )  // flush all

// Cache
jpkcom_postfilter_cache_get( $key, $found )
jpkcom_postfilter_cache_set( $key, $value, $ttl )
jpkcom_postfilter_cache_flush_group()
jpkcom_postfilter_transient_get( 'terms_category' )
jpkcom_postfilter_transient_set( 'terms_category', $data )

// Templates
jpkcom_postfilter_locate_template( 'partials/filter/filter-bar.php' )
jpkcom_postfilter_get_template_part( 'partials/filter/filter-bar', '', $args )
jpkcom_postfilter_get_template_html( 'partials/list/list-cards', '', $args )

// URL helpers
jpkcom_postfilter_get_filter_url( $base_url, $active_filters )
jpkcom_postfilter_get_archive_base_url( $post_type )
jpkcom_postfilter_get_active_filters()
jpkcom_postfilter_build_filter_url( $base, $filters )
jpkcom_postfilter_is_filter_request()

// Filter groups
jpkcom_postfilter_get_filter_groups_enabled()
jpkcom_postfilter_get_terms_for_group( $group, $active_filters )

Filters

• jpkcom_postfilter_ability_meta( array $meta, string $ability_name ) — adjust the meta of an ability before registration. Set show_in_rest to false to hide it from the REST API, or mcp.public to false to hide it from MCP clients.
• jpkcom_postfilter_ability_capability( string $capability, string $ability_name ) — the capability required to run an ability. Defaults to read, which covers every logged-in user. Raise it to edit_posts to restrict bulk machine-readable access to published content.

---

FAQ

Does this plugin work with custom post types? Yes. Any post type registered in WordPress can be enabled in Post Filter → General.

Does it work with custom taxonomies? Yes. All registered taxonomies (including custom ones) appear in the Filter Groups configuration. You can also create new taxonomies directly from the Filter Groups page without writing any code.

Does filtering work without JavaScript? Yes. Each filter term is a regular <a> link. Without JS the page reloads with the new filter URL. With JS, only the results zone is updated via AJAX.

Will the filter URLs be indexed by search engines? Each filter combination has a unique, crawlable URL. The plugin registers WordPress rewrite rules and sets canonical URLs to avoid duplicate content.

Can I place shortcodes on any page? No — shortcodes must be placed on the archive page for the configured post type (via a page builder/FSE template, or by using a WordPress page as the "Posts Page"). On an arbitrary custom page the filter links will navigate away to the archive URL. See the Shortcodes section above for details. The same applies to Gutenberg blocks, Elementor widgets, and Oxygen elements.

Can I use multiple filter instances for different post types on the same page? Yes. Each shortcode/block/widget set is paired by post_type attribute. The JS matches [data-jpkpf-filter-bar][data-jpkpf-post-type="X"] with [data-jpkpf-results][data-jpkpf-post-type="X"].

Do the Gutenberg blocks work in the Full Site Editor (FSE)? Yes. All three blocks work in FSE templates. The pagination block can be placed above and/or below the list block — the plugin pre-scans the template block tree to ensure correct query availability regardless of block order.

Does the plugin require Elementor or Oxygen Builder? No. Page builder support is optional. Elementor widgets are only loaded when Elementor is active, and Oxygen elements are only loaded when Oxygen Builder is active. The plugin works independently with auto-inject mode, shortcodes, or Gutenberg blocks.

How do I clear the plugin cache? Go to Post Filter → Cache and click one of the Clear Cache buttons. Caches are also invalidated automatically when posts or terms are saved or deleted.

How do I change the URL segment from "filter" to something else? Change the URL Endpoint in Post Filter → General, then click Flush Rewrite Rules (or visit Settings → Permalinks and save).

How do I disable the plugin's CSS entirely? Set Stylesheet Mode to "Disabled" in Post Filter → Layout & Design → Advanced. You are then fully responsible for all styling.

---

Changelog

1.4.4

• Fixed: with an HTML-minifying optimisation plugin active, every filter click returned an empty response and the list reported "No posts found." — on a site whose posts all still matched. The AJAX fragment was cut out of the rendered page along HTML comment markers, and minifiers remove HTML comments; Autoptimize does so with its stock settings, and its output buffer runs before this plugin's. Measured on the verification install: 18 300 bytes with Autoptimize inactive, 0 bytes with it active, 18 300 again with its HTML optimisation switched off. The markers are now empty `