= v160222 = - **Announcement: ZenCache is changing its name to Comet Cache!** Learn more about this upcoming change [here](https://cometcache.com/r/announcing-comet-cache-formerly-zencache/). - **Announcement: This version of ZenCache requires PHP 5.4+.** As announced in the previous release, the minimum PHP version required to run ZenCache / Comet Cache has changed to PHP 5.4+ as of December 1st, 2015. Please see announcement with further details: [New Minimum PHP Version: PHP 5.4](http://zencache.com/r/new-minimum-php-version-php-5-4/) - **Announcement: This version of ZenCache does not support the PHP APC Extension**. As announced in the previous release, ZenCache / Comet Cache no longer runs with the PHP APC extension enabled as of December 1st, 2015. Please see announcement with further details: [PHP APC Extension No Longer Supported](http://zencache.com/r/php-apc-extension-no-longer-supported/) - **Announcement: After March 1st, 2016 ZenCache / Comet Cache will require PHP Multibyte String support.** The `mbstring` extension provides Multibyte String support to PHP and is required to properly handle UTF-8 characters, which many sites now use. Without Multibyte String support, caching will be unstable. For that reason we are requiring the `mbstring` extension to improve reliability when caching and to prevent your site from experiencing unforeseen issues in the future. - **Announcement: Restructured Codebase**. The entire ZenCache Lite codebase has been restructured to improve performance, enhance flexibility, and make it easier to build in new features! This release of ZenCache Lite has been built from the ZenCache Pro codebase, which is more polished and up-to-date. This release includes many changes and improvements that were released as part of ZenCache Pro releases over the past 6 months and are now being included in the Lite version. See the full changelog below for a complete list of changes. - **New Feature!** A new watered-down Regular Expression syntax is now supported in several existing ZenCache features, including XML Sitemap Patterns, URI Exclusion Patterns, HTTP Referrer Exclusion Patterns, and User-Agent Exclusion Patterns. (It is also supported in the Pro-only Custom URLs to Auto-Clear, and the HTML Compressor CSS Exclusion Patterns and JavaScript Exclusion Patterns.) This new syntax greatly increases the power and flexibility of each of these features and makes things possible like the much-requested ability to Auto-Clear the Home Page or Posts Page of a site whenever a post cache is cleared. For more information on this new watered-down Regular Expression syntax, [this KB Article](http://zencache.com/r/watered-down-regex-syntax/). Props @kristineds @jaswsinc. See [Issue #191](https://github.com/websharks/zencache/issues/191). - **Bug Fix**: Fixed a bug with clearing cache files for paginated pages where the `pagination_base` had been changed from the default `page` to something else (e.g., a translated string). The WP Rewrite API is now used to include `pagination_base` and `comments_pagination_base` when building paths to cache files to determine which cache files should be cleared. Props @renzms. See [Issue #607](https://github.com/websharks/zencache/issues/607). - **Bug Fix**: This release attempts to resolve reports of Error 500 and Internal Server Error issues when running with PHP 5.6 + OPcache. Instead of clearing the entire Opcode cache whenever the plugin options are saved, we only invalidate the `advanced-cache.php` file, which is rebuilt each time you update your configuration options. Props @jaswsinc. Also props to @MarioKnight and @CotswoldPhoto for helping us narrow this down. See [Issue #624](https://github.com/websharks/zencache/issues/624). - **Bug Fix**: Fixed an issue where a PHP Notice was generated when an inactive WordPress component was being upgraded. This issue did not have any adverse affect on the site, but this fix resolves the issue so that the notice won't appear in PHP logs. See [Issue #589](https://github.com/websharks/zencache/issues/589). - **Bug Fix**: Fixed a bug where a commented-out `WP_CACHE` definition in `wp-config.php` (such as what WP Super Cache leaves behind) was being incorrectly ignored and resulted in caching being silently disabled. Props @davidfavor. See [Issue #591](https://github.com/websharks/zencache/issues/591). - **Bug Fix**: Fixed a bug where in some scenarios a page might not be cached due to a stray `AUTH_COOKIE` or `SECURE_AUTH_COOKIE` cookie, even when the user is not logged in. Props @jaswsinc @renzms. See [Issue #592](https://github.com/websharks/zencache/issues/592). - **Bug Fix**: Fixed an issue related to a popular NGINX server configuration (`try_files $uri $uri/ /index.php?q=$uri&$args;`) that was preventing the entire site from being cached. ZenCache disables caching by default for all requests that include a query string (see _Dashboard → ZenCache → Plugin Options → GET Requests_) and this particular NGINX configuration passes _all_ requests to WordPress with a `?q=` query variable, which was resulting in ZenCache disabling caching on all pages. This release implements better detection for NGINX and works around this scenario. Props @jaswsinc. See [Issue #561](https://github.com/websharks/zencache/issues/561). - **Bug Fix**: Fixed a bug where, in some rare cases, `wp-config.php` would end up with two `WP_CACHE` definitions. Props @jaswsinc. See [Issue #509](https://github.com/websharks/zencache/issues/509). - **Bug Fix**: Saving a Post as a Draft was incorrectly purging XML Sitemap cache files. Props @jaswsinc. See [Issue #368](https://github.com/websharks/zencache/issues/368). - **Bug Fix**: Fixed a bug in the Dynamic Version Salt filter that was generating PHP notices and warnings. See [Issue #522](https://github.com/websharks/zencache/issues/522). - **Bug Fix**: Fixed an issue with backwards compatibility that was preventing some AC Plugins from working properly. See [Issue #514](https://github.com/websharks/zencache/issues/514). - **Bug Fix**: Fixed a bug where saving a Post/Page as a Draft as a user with an Editor role would unnecessarily clear the Home Page cache. See [Issue #625](https://github.com/websharks/zencache/issues/625). - **Multisite Bug Fix**: Fixed a bug where the Clear Cache button wouldn't clear Child-Site Logged-In User Home Page cache files on WordPress Multisite Networks. Props @jaswsinc. See [Issue #409](https://github.com/websharks/zencache/issues/409) - **Multisite Bug Fix**: Fixed a bug where the Home Page cache was not clearing on Child Sites in a Multisite Network. Props @jaswsinc. See [Issue #409](https://github.com/websharks/zencache/issues/409) - **Multisite Bug Fix**: Fixed a bug with 404 Request caching on Multisite Networks where ZenCache Pro was not considering that each child blog in a multisite network will have its own 404 error page. Props @jaswsinc. See [Issue #539](https://github.com/websharks/zencache/issues/539). - **Multisite Bug Fix**: Fixed a bug where clearing the cache from the main site of a multisite network, when there are child blogs in sub-directories, resulted in all child blogs being cleared from the cache, not just the main site as would be expected. This has been resolved and only the main site is cleared when clicking the Clear Cache button. Note that the Wipe Cache button can still be used to clear the cache for all sites in a Multisite Network. Props @jaswsinc. See [Issue #540](https://github.com/websharks/zencache/issues/540). - **Multisite Bug Fix**: Fixed a bug where Wiping the cache on a multisite network resulted in the very next page view being cached incorrectly. Props @jaswsinc. See [Issue #541](https://github.com/websharks/zencache/issues/541). - **Multisite Bug Fix**: Fixed a bug where when ZenCache was Network Activated the plugin settings link would show up in the plugins list for the Main Site and would lead to a 404 error. The settings link is now only shown when viewing the plugins list from the Network Admin. Props @jaswsinc. See [Issue #675](https://github.com/websharks/zencache/issues/675). - **Enhancement**: Added support-related links to the plugin options page. Props @renzms. See [Issue #612](https://github.com/websharks/zencache/issues/612#issuecomment-186827661). - **Enhancement**: It's now possible to override the ZenCache Nonce exclusion globally (dangerous) or only for Logged-In Users (safer). Please see [this article](http://zencache.com/r/kb-article-what-are-wordpress-nonces-and-why-are-they-not-cache-compatible/) for full details. [Issue #637](https://github.com/websharks/zencache/issues/637). - **Enhancement**: Improved WP Cron-related configuration and validation of custom cron schedules. See [PR #197](https://github.com/websharks/zencache-pro/pull/197). - **Enhancement**: ZenCache now clears the cache whenever a WordPress plugin is activated or deactivated. Many WordPress plugins change content on the front-end of the site, so this enhancement ensures that an old cache file is never served to visitors. If you want to disable this automatic behavior, see [this article](http://zencache.com/kb-article/how-do-i-prevent-zencache-from-clearing-the-cache-upon-plugin-activation-or-deactivation/). Props @renzms. See [Issue #424](https://github.com/websharks/zencache/issues/424). - **Enhancement**: When activating ZenCache for the first time, a new Dashboard message now includes a helpful link to the options page to enable caching and review the options. Props @kristineds. See [Issue #112](https://github.com/websharks/zencache/issues/112). - **Enhancement**: The automatic Cache Cleanup schedule that cleans up (deletes) expired/stale cache files has been changed from once every day to once every hour. Running the cleanup hourly makes ZenCache smarter when configured in certain ways and saves disk space. Props @kristineds. See [Issue #472](https://github.com/websharks/zencache/issues/472). - **Enhancement**: When the Cache Directory location is changed, ZenCache now cleans up the old Cache Directory and any old cache files instead of leaving them behind. Props @clavaque @renzms. See [Issue #580](https://github.com/websharks/zencache/issues/580). - **Enhancement**: Added a new API Function that allows a site owner to clear the cache for a specific URL via `zencache::clearUrl($url);`. See [this article](http://zencache.com/kb-article/clearing-the-cache-dynamically/#toc-988085ad) for further details. Props @kristineds. See [Issue #590](https://github.com/websharks/zencache/issues/590). - **Enhancement**: Improved the HTML Notes generated by ZenCache when s2Member (a membership plugin for WordPress) is specifically disabling caching. s2Member automatically disables caching on certain pages that are required to remain dynamic. The HTML Notes generated by ZenCache now explain when this is happening. Props @renzms. See [Issue #504](https://github.com/websharks/zencache/issues/504). - **Enhancement**: Manual Cache Clearing options have now been separated from Automatic Cache Clearing options inside the ZenCache Plugin Options to improve the differentiation between these. - **Enhancement**: New icons in the ZenCache Plugin Options help improve the visual representation of each panel. - **Enhancement**: The installed plugin version is now shown at the top of the ZenCache Options Page. Props @renzms. See [Issue #502](https://github.com/websharks/zencache/issues/502). - **Enhancement**: New transition in/out effects on the Cache Cleared Dashboard notifications. Props @jaswsinc. See [Issue #538](https://github.com/websharks/zencache/issues/538). - **Enhancement**: Improved compatibility with any Custom Post Type that uses hierarchies. Props @jaswsinc. - **Akismet Compatibility:** ZenCache no longer caches pages that contain `akismet_comment_nonce` in the markup. This ensures that a page that contains a time-sensitive `nonce` value does not get cached. Props @kristineds and @jaswsinc. See [Issue #601](https://github.com/websharks/zencache/issues/601). - **Akismet Compatibility:** ZenCache now automatically disables the Akismet Comment Nonce using [the `akismet_comment_nonce` filter](https://github.com/git-mirror/wordpress-akismet/blob/2.5.6/akismet.php#L333), which improves compatibility between Akismet and the page caching functionality provided by ZenCache. This ensures that pages do not contain time-sensitive `nonce` values that should not be cached. If you'd like to revert this behavior, please see [this article](http://zencache.com/kb-article/how-do-i-prevent-zencache-from-disabling-the-akismet-comment-nonce/). Props @kristineds and @jaswsinc. See [Issue #601](https://github.com/websharks/zencache/issues/601). - **Akismet Compatibility**: Fixed a bug with Akismet compatibility where ZenCache was not properly disabling the Akismet Comment Nonce, which resulted in pages being unnecessarily excluded from the cache due to the presence of the `akismet_comment_nonce` in the markup. Props @Kalfer. See [Issue #642](https://github.com/websharks/zencache/issues/642). - **WooCommerce Compatibility:** This release improves compatibility with the WooCommerce Product Stock feature. When the Product Stock changes, ZenCache will now clear the cache file for the associated Product to ensure that the stock quantity that appears on the site remains up-to-date. See [Issue #597](https://github.com/websharks/zencache/issues/597). - **Multisite Domain Mapping Compatibility**: ZenCache is now fully compatible with the [WordPress MU Domain Mapping plugin](https://wordpress.org/plugins/wordpress-mu-domain-mapping/), including Multisite Networks using domain mapping on top-level domains, sub-domains, and sub-directories. Multiple variations of each site spread across an unlimited number of domain mappings and/or the original blog domain/path is also supported. All Pro-only features, including the Auto-Cache Engine, Static CDN Filters, and HTML Compression, are also now compatible with domain mapping. Props @jaswsinc. See [Issue #339](https://github.com/websharks/zencache/issues/339). - **bbPress Compatibility**: This release greatly improves compatibility with bbPress. Events like creating a new Forum, creating a new Topic, and posting a reply to a Topic (including threaded replies), now properly clear the necessary cache files to ensure that cached bbPress pages remain up-to-date. Props @jaswsinc. See [Issue #168](https://github.com/websharks/zencache/issues/168). - **bbPress Compatibility:** This release improves compatibility with bbPress when ZenCache Logged-In User caching is enabled. In this scenario, bbPress may generate links for Admins that contain time-sensitive `_wpnonce` values which could expire if cached and result in certain admin-related actions failing. ZenCache no longer caches pages that contain `_wpnonce` in the markup. This ensures that pages containing time-sensitive `nonce` values are not cached. Props @kristineds, @jaswsinc, and @clavaque. See [Issue #601](https://github.com/websharks/zencache/issues/601). - **New Pro Features:** This release updates the Pro Preview to include several new Pro features that have been added over the past 6 months, including the ability to clear the PHP OPCache whenever manually clearing the cache (_ZenCache Options → Manual Cache Clearing → Clear the PHP OPCache Too?_), clear the CDN Cache whenever manually clearing the cache (_ZenCache Options → Manual Cache Clearing → CDN Cache Clear the CDN Cache Too?_), disable cache expiration if the server load average is high (_ZenCache Options → Cache Expiration Time → Disable Cache Expiration If Server Load Average is High_), the ability to specify which WordPress Roles/Capabilities are allowed to clear the cache from the WordPress Admin bar (_ZenCache Options → Manual Cache Clearing → Also allow others to clear the cache from their Admin Bar?_), a completely new Cache Statistics feature that allows you to monitor the health and status of your cache (_ZenCache → Stats / Charts_), the ability to specify a list of Custom URLs whose cache files should be cleared whenever ZenCache detects that a Post/Page cache should be cleared (_ZenCache Options → Automatic Cache Clearing → Misc. Auto-Clear Options → Auto-Clear a List of Custom URLs Too?_), a new menu of Clear Cache options in the Admin Bar that allows you to clear the cache for just the Home Page, the Current URL, a Specific URL, PHP's OPCache, or the CDN Cache (_ZenCache Options → Plugin Options → Manual Cache Clearing_), the ability to customize the Cache Cleanup Schedule and set your own schedule (_ZenCache Options → Manual Cache Clearing → Cache Cleanup Schedule_), the ability to configure the Pro Plugin Updater to check for Beta versions, an option to clear Expired WordPress Transients, and URI Exclusion Patterns for Client-Side Caching. = v160103 = - **Bug Fix**: Fixed an issue that was unexpectedly producing "Failed to update your /.htaccess file" error messages. The `.htaccess` routines are now more intelligent and take into consideration which plugin options are enabled and which options require updating the `.htaccess` file. This also improves performance by avoiding unnecessary read/writes to the `.htaccess` file. Props @patdumond. See [Issue #641](https://github.com/websharks/zencache/issues/641). - **Bug Fix**: When `allow_url_fopen` is disabled via the PHP configuration, the Auto-Cache Engine is unable to read the XML Sitemap and was silently failing with only PHP Warning in the PHP error log. The Auto-Cache Engine currently requires [PHP URL-aware fopen wrappers](http://zencache.com/r/allow_url_fopen/). A new Dashboard notice displays an error message when `allow_url_fopen` is disabled and prevents the Auto-Cache Engine from attempting to run. See [Issue #644](https://github.com/websharks/zencache/issues/644). - **Bug Fix**: Fixed an Auto-Cache Engine bug that was producing false-positive Dashboard errors related to timeouts: "Problematic XML Sitemap URL - WP_Http says: Operation timed out after 5001 milliseconds with 0 bytes received." Due to the way ZenCache was checking the XML Sitemap URL more than necessary, timeouts were more likely to occur. We now only check the URL repeatedly when a failure has been encountered. If the URL is confirmed as working, we don't check the URL again until the Auto-Cache Engine runs (every 15 minutes by default) or until the Plugin Options are saved. If you are still seeing timeout errors after this update, please see [this article](http://zencache.com/kb-article/why-am-i-seeing-auto-cache-engine-timeout-errors/). See [Issue #643](https://github.com/websharks/zencache/issues/643). - **Bug Fix**: Fixed an Auto-Cache Engine bug where ZenCache would would check both the non-SSL (`http://`) and the SSL (`https://`) version of the XML Sitemap URL when the Site Address was configured to use SSL. See [Issue #643](https://github.com/websharks/zencache/issues/643). - **Enhancement**: It's now possible to override the ZenCache Nonce exclusion globally (dangerous) or only for Logged-In Users (safer). Please see [this article](http://zencache.com/r/kb-article-what-are-wordpress-nonces-and-why-are-they-not-cache-compatible/) for full details. [Issue #637](https://github.com/websharks/zencache/issues/637). - **Akismet Compatibility**: Fixed a bug with Akismet compatibility where ZenCache was not properly disabling the Akismet Comment Nonce, which resulted in pages being unnecessarily excluded from the cache due to the presence of the `akismet_comment_nonce` in the markup. Props @Kalfer. See [Issue #642](https://github.com/websharks/zencache/issues/642). = v151220 = - **New Feature!**: It's now possible to customize the Cache Cleanup Schedule and set your own schedule in _ZenCache → Plugin Options → Manual Cache Clearing → Cache Cleanup Schedule_. ZenCache uses [`wp_get_schedules()`](https://codex.wordpress.org/Function_Reference/wp_get_schedules) when generating the list of available schedules, which makes it possible to create your own custom cron schedule using a plugin like WP Crontrol and use that to define a custom Cache Cleanup Schedule. Props @kristineds. See [Issue #472](https://github.com/websharks/zencache/issues/472). - **New Feature!** It's now possible to configure the Pro Plugin Updater to check for Beta versions (Release Candidates) of the plugin. See _ZenCache → Plugin Updater → Beta Testers_. We publish Release Candidates a week or so before official releases to allow for additional testing and early preview of upcoming features and bug fixes. If you're not already on our Beta Testers mailing list, you can signup [here](http://zencache.com/r/zencache-beta-testers-list/). Props @kristineds. See [Issue #352](https://github.com/websharks/zencache/issues/352). - **New Feature!** It's now possible to clear [Expired WordPress Transients](https://codex.wordpress.org/Transients_API) from the Clear Cache Option Menu in the WordPress Admin Bar. The WordPress Transients API has no functionality to automatically clean up expired transients; doing so is left for plugin authors and we've found that very few plugins that use the Transient API actually clean up expired transients properly, which can lead to your database being full of expired transient data that is no longer used. Props @kristineds. See [Issue #459](https://github.com/websharks/zencache/issues/459). - **New Feature!** Client-Side Caching now includes a new URI Exclusion Patterns for Client-Side Caching, allowing you to exclude specific URIs from being cached by a client-side browser when Client-Side Caching is enabled. Props @renzms. See [Issue #498](https://github.com/websharks/zencache/issues/498). - **Bug Fix**: Fixed a bug that was generating a "Failed to update your `/.htaccess` file" error message. The routines that update your `.htaccess` file were failing if your `.htaccess` file already contained the word "ZenCache" (case-insensitive). See [Issue #617](https://github.com/websharks/zencache/issues/617) and [Issue #620](https://github.com/websharks/zencache/issues/620). - **Bug Fix**: Fixed a bug that in some scenarios could cause custom `.htaccess` rules to be lost if your `.htaccess` file was using the exact same comment start and end markers as ZenCache (`# BEGIN ZenCache` and `# END ZenCache`). If you were using those exact same start and end markers, ZenCache was replacing whatever was between them with a copy of the ZenCache `.htaccess` rules. ZenCache now uses a unique marker (`WmVuQ2FjaGU`) to identify its own code blocks inside your `.htaccess` file. See [Issue #620](https://github.com/websharks/zencache/issues/620). - **Bug Fix**: Fixed a bug with clearing cache files for paginated pages where the `pagination_base` had been changed from the default `page` to something else (e.g., a translated string). The WP Rewrite API is now used to include `pagination_base` and `comments_pagination_base` when building paths to cache files to determine which cache files should be cleared. Props @renzms. See [Issue #607](https://github.com/websharks/zencache/issues/607). - **Bug Fix**: Fixed a bug with the Static CDN Filters that affected sites using a permalink structure that ended with `.htm` or `.html`. This bug was supposed to be fixed back in v151002 but another bug prevented the fix from working properly. This release fixes the issue once and for all. See [Issue #495](https://github.com/websharks/zencache/issues/495#issuecomment-160324313). - **Bug Fix**: With Logged-In User caching enabled, there were some scenarios where the user cache was being cleared on every page load when a user was logged in. ZenCache now hooks into `updated_user_metadata` instead of `update_user_metadata` to clear a specific user cache. Props @kristineds. See [Issue #623](https://github.com/websharks/zencache/issues/623). - **Bug Fix**: Fixed a bug where the Auto-Cache Engine cron event would disappear in some scenarios. Props @patdumond, @MarioKnight. See [Issue #613](https://github.com/websharks/zencache/issues/613). - **Bug Fix**: ZenCache no longer caches any pages that contain `_wpnonce` in the markup. This ensures that pages containing time-sensitive `nonce` values are not cached. Props @kristineds and @jaswsinc. See [Issue #601](https://github.com/websharks/zencache/issues/601). - **Bug Fix**: This release attempts to resolve reports of Error 500 and Internal Server Error issues when running with PHP 5.6 + OPcache. Instead of clearing the entire Opcode cache whenever the plugin options are saved, we only invalidate the `advanced-cache.php` file, which is rebuilt each time you update your configuration options. Props @jaswsinc. Also props to @MarioKnight and @CotswoldPhoto for helping us narrow this down. See [Issue #624](https://github.com/websharks/zencache/issues/624). - **Bug Fix**: Fixed a bug where ZenCache could inadvertently corrupt the `.htaccess` file if it contained invalid UTF-8 characters. This has been fixed by first checking the `.htaccess` file for invalid UTF-8 characters via `wp_check_invalid_utf8()`. See [Issue #633](https://github.com/websharks/zencache/issues/633#issuecomment-165493039). - **Enhancement**: Improved WP Cron-related configuration and validation of custom cron schedules. See [PR #197](https://github.com/websharks/zencache-pro/pull/197). - **Enhancement**: ZenCache now clears the cache whenever a WordPress plugin is activated or deactivated. Many WordPress plugins change content on the front-end of the site, so this enhancement ensures that an old cache file is never served to visitors. If you want to disable this automatic behavior, see [this article](http://zencache.com/kb-article/how-do-i-prevent-zencache-from-clearing-the-cache-upon-plugin-activation-or-deactivation/). Props @renzms. See [Issue #424](https://github.com/websharks/zencache/issues/424). - **Enhancement**: The Auto-Cache Engine diagnostic reporting for XML Sitemap-related errors has been greatly improved. The Dashboard notice now explains exactly what error is occurring when the Auto-Cache Engine attempts to verify that the XML Sitemap exists. Props @jaswsinc. See [Issue #615](https://github.com/websharks/zencache/issues/615) and [Issue #618](https://github.com/websharks/zencache/issues/618). - **Enhancement**: Auto-Cache Engine XML Sitemap error checking is now more intelligent. When configured, the XML Sitemap URL is now checked upon every `admin_init` to verify that the XML Sitemap is accessible and valid. If a previous error has been fixed, the error message will disappear immediately instead of taking 15 minutes (the Auto-Cache Engine run cycle). See [Issue #616](https://github.com/websharks/zencache/issues/616). - **Enhancement**: Static CDN Filters are no longer applied by default for Logged-In Users. This was causing some confusion because Logged-In User caching is disabled by default. There is no harm in applying Static CDN Filters to all users (logged-in or not logged-in), in fact we recommend it, however we now disable this functionality by default to avoid confusion. A new option allows you to control this behavior and enable Static CDN Filters for Logged-In users; see _ZenCache → Logged-In Users → Static CDN Filters Enabled for Logged-In Users & Comment Authors?_ Props @kristineds, @lkraav, and @isaumya. See [Issue #486](https://github.com/websharks/zencache/issues/486). - **Enhancement**: The Static CDN Filters now attempt to obey the `ZENCACHE_ALLOWED` and `DONOTCACHEPAGE` constants so that Static CDN Filters are not applied when caching is disabled. However, due to the way Static CDN Filters are implemented this is not always reliable. If you need to programmatically disable Static CDN Filters, see [this article](http://zencache.com/kb-article/how-do-i-disable-static-cdn-filters-via-php/). See [Issue #628](https://github.com/websharks/zencache/issues/628). - **Enhancement**: When activating ZenCache for the first time, a new Dashboard message now includes a helpful link to the options page to enable caching and review the options. Props @kristineds. See [Issue #112](https://github.com/websharks/zencache/issues/112). - **Enhancement**: The automatic Cache Cleanup schedule that cleans up (deletes) expired/stale cache files has been changed from once every day to once every hour. Running the cleanup hourly makes ZenCache smarter when configured in certain ways and saves disk space. Props @kristineds. See [Issue #472](https://github.com/websharks/zencache/issues/472). - **Enhancement:** The new default value for "Clear the PHP OPcache Too?" when clearing the cache manually is now disabled. Instead of having this option enabled by default, we automatically invalidate only the `advanced-cache.php` file in PHP's opcode cache whenever you update your configuration options, which allows ZenCache to function as expected. That was the most important reason for needing to clear the opcode cache in previous versions. Props @jaswsinc. Also props to @MarioKnight and @CotswoldPhoto for helping us narrow this down. See [Issue #624](https://github.com/websharks/zencache/issues/624). - **Enhancement**: Improved `.htaccess` utilities so that an exclusive lock is acquired when reading+writing to the file. This helps avoid inadvertently corrupting the `.htaccess` file in scenarios where another process might be reading/writing to it at the same time. See [Issue #633](https://github.com/websharks/zencache/issues/633). - **Multisite Enhancement**: The Auto-Cache Engine has a new configuration option when running on WP Multisite Networks that allows you to define whether or not the Auto-Cache Engine should look for XML Sitemaps on each of the child blogs. This now defaults to being off; i.e., by default, child blogs are no longer checked. Props @jaswsinc. See [Issue #618](https://github.com/websharks/zencache/issues/618#issuecomment-158695842). - **Multisite Enhancement**: The Auto-Cache Engine XML Sitemap diagnostic reporting is now always disabled for child blogs and only errors related to a primary sitemap location are displayed on the Dashboard. Props @jaswsinc. See [Issue #618](https://github.com/websharks/zencache/issues/618#issuecomment-158695842). - **bbPress Compatibility:** This release improves compatibility with bbPress when ZenCache Logged-In User caching is enabled. In this scenario, bbPress may generate links for Admins that contain time-sensitive `_wpnonce` values which could expire if cached and result in certain admin-related actions failing. ZenCache no longer caches pages that contain `_wpnonce` in the markup. This ensures that pages containing time-sensitive `nonce` values are not cached. Props @kristineds, @jaswsinc, and @clavaque. See [Issue #601](https://github.com/websharks/zencache/issues/601). - **Akismet Compatibility:** ZenCache no longer caches pages that contain `akismet_comment_nonce` in the markup. This ensures that a page that contains a time-sensitive `nonce` value does not get cached. Props @kristineds and @jaswsinc. See [Issue #601](https://github.com/websharks/zencache/issues/601). - **Akismet Compatibility:** ZenCache now automatically disables the Akismet Comment Nonce using [the `akismet_comment_nonce` filter](https://github.com/git-mirror/wordpress-akismet/blob/2.5.6/akismet.php#L333), which improves compatibility between Akismet and the page caching functionality provided by ZenCache. This ensures that pages do not contain time-sensitive `nonce` values that should not be cached. If you'd like to revert this behavior, please see [this article](http://zencache.com/kb-article/how-do-i-prevent-zencache-from-disabling-the-akismet-comment-nonce/). Props @kristineds and @jaswsinc. See [Issue #601](https://github.com/websharks/zencache/issues/601). - **WooCommerce Compatibility:** This release improves compatibility with the WooCommerce Product Stock feature. When the Product Stock changes, ZenCache will now clear the cache file for the associated Product to ensure that the stock quantity that appears on the site remains up-to-date. See [Issue #597](https://github.com/websharks/zencache/issues/597). = v151114 = - **Announcement: The next version of ZenCache will require PHP 5.4+.** As of December 1st, 2015, the minimum PHP version required to run ZenCache will change to PHP 5.4+. This release of ZenCache will be the last version to support PHP 5.3. Please see announcement with further details: [New Minimum PHP Version: PHP 5.4](http://zencache.com/r/new-minimum-php-version-php-5-4/) - **Announcement: The next version of ZenCache will not support the PHP APC Extension**. As of December 1st, 2015, ZenCache will no longer run with the PHP APC extension enabled. Please see announcement with further details: [PHP APC Extension No Longer Supported](http://zencache.com/r/php-apc-extension-no-longer-supported/) - **New Feature!** The Clear Cache button in the Admin Bar now includes a sub-menu with several new options for clearing the cache from anywhere on your site. You can clear the cache for just the Home Page, the Current URL, a Specific URL, PHP's OPCache (if active), or the CDN Cache (when Static CDN Filters are configured). This menu comes in two flavors and can be customized (or disabled entirely) inside _ZenCache → Plugin Options → Manual Cache Clearing_. Props @jaswsinc. See [Issue #596](https://github.com/websharks/zencache/issues/596#issuecomment-152786080). - **New Feature!** It's now possible to specify a list of Custom URLs whose cache files should be cleared whenever you update a Post/Page, approve a Comment, or make other changes where ZenCache detects that a Post/Page cache should be cleared to keep your site up-to-date. See _ZenCache → Plugin Options → Automatic Cache Clearing → Misc. Auto-Clear Options → Auto-Clear a List of Custom URLs Too?_ Props @kristineds. See [Issue #111](https://github.com/websharks/zencache/issues/111). - **New Feature!** A new watered-down Regular Expression syntax is now supported in several existing ZenCache features, including the new list of Custom URLs to Auto-Clear, URI Exclusion Patterns, HTTP Referrer Exclusion Patterns, User-Agent Exclusion Patterns, and the HTML Compressor CSS Exclusion Patterns and JavaScript Exclusion Patterns. This new syntax greatly increases the power and flexibility of each of these features and makes things possible like the much-requested ability to Auto-Clear the Home Page or Posts Page of a site whenever a post cache is cleared. For more information on this new watered-down Regular Expression syntax, [this KB Article](http://zencache.com/r/watered-down-regex-syntax/). Props @kristineds @jaswsinc. See [Issue #191](https://github.com/websharks/zencache/issues/191). - **Bug Fix**: Fixed a bug with Static CDN Filters and Cross-Origin Resource Sharing (CORS) that was generating a "Cross-Origin Request Blocked" error. ZenCache will now update the root `.htaccess` file to include a `Header set Access-Control-Allow-Origin "*"` rule for `ttf`, `ttc`, `otf`, `eot`, `woff`, `woff2`, `font.css`, `css`, and `js` files whenever the Static CDN Filters are enabled. This is necessary to avoid "Cross-Origin Request Blocked" errors. Note that if you are already experiencing this error, you should create and configure a new CDN hostname to resolve the issue. In our tests it appears that some CDNs are caching the initial header response received by the server, which means it's necessary to send the `Access-Control-Allow-Origin` header _before_ configuring the Static CDN Filters with a CDN hostname. See [Issue #427](https://github.com/websharks/zencache/issues/427#issuecomment-121774596). - **Bug Fix**: Removed `eot,ttf,otf,woff` font extensions from the Static CDN Filter Blacklisted Extensions. These were added in a previous release in an attempt to resolve an issue with Cross-Origin Resource Sharing (CORS), however now that the HTML Compressor has been updated to work with Static CDN Filters, the CSS compressed by the HTML Compressor is now served from the CDN. Fonts are most likely to be referenced by CSS, which is static. So when Static CDN Filters are applied, the CSS is getting moved to the CDN and the fonts are then expected to live on the CDN too. By excluding them from the Static CDN Filter, we were creating a problem instead of solving one. This release removes the font extensions from the default Blacklisted Extensions so that fonts can be hosted on the CDN alongside the CSS that references them. See [Issue #427](https://github.com/websharks/zencache/issues/427#issuecomment-121777790). - **Bug Fix**: Fixed a bug related to updating plugins with WP-CLI on a site that was running ZenCache Pro. While ZenCache Pro updates must still be done through the ZenCache Pro Updater inside the Dashboard, updating other plugins via WP-CLI was generating a harmless ZenCache exception: "Invalid argument; host token empty!". With this fix, ZenCache will properly detect when WP-CLI is running to avoid these errors. Props @MarioKnight @renzms. See [Issue #563](https://github.com/websharks/zencache/issues/563). - **Bug Fix**: Fixed a bug where post previews were being cached when Logged-In User Caching and GET Request caching were both enabled (both are disabled by default). This release now detects previews in this scenario and excludes those requests from being cached. Props @clavaque @kristineds. See [Issue #583](https://github.com/websharks/zencache/issues/583). - **Bug Fix**: Fixed an issue where a PHP Notice was generated when an inactive WordPress component was being upgraded. This issue did not have any adverse affect on the site, but this fix resolves the issue so that the notice won't appear in PHP logs. See [Issue #589](https://github.com/websharks/zencache/issues/589). - **Bug Fix**: Fixed a bug where a commented-out `WP_CACHE` definition in `wp-config.php` (such as what WP Super Cache leaves behind) was being incorrectly ignored and resulted in caching being silently disabled. Props @davidfavor. See [Issue #591](https://github.com/websharks/zencache/issues/591). - **Bug Fix**: Fixed a bug where in some scenarios a page might not be cached due to a stray `AUTH_COOKIE` or `SECURE_AUTH_COOKIE` cookie, even when the user is not logged in. Props @jaswsinc @renzms. See [Issue #592](https://github.com/websharks/zencache/issues/592). - **Enhancement**: Excluded several unnecessary files from the plugin zip file that were being used during the build process but were not necessary to run the plugin. Props @bridgeport. See [Issue #579](https://github.com/websharks/zencache/issues/579). - **Enhancement**: When the Cache Directory location is changed, ZenCache now cleans up the old Cache Directory and any old cache files instead of leaving them behind. Props @clavaque @renzms. See [Issue #580](https://github.com/websharks/zencache/issues/580). - **Enhancement**: Added a new API Function that allows a site owner to clear the cache for a specific URL via `zencache::clearUrl($url);`. See [this article](http://zencache.com/kb-article/clearing-the-cache-dynamically/#toc-988085ad) for further details. Props @kristineds. See [Issue #590](https://github.com/websharks/zencache/issues/590). - **Enhancement**: Improved the HTML Notes generated by ZenCache when s2Member (a membership plugin for WordPress) is specifically disabling caching. s2Member automatically disables caching on certain pages that are required to remain dynamic. The HTML Notes generated by ZenCache now explain when this is happening. Props @renzms. See [Issue #504](https://github.com/websharks/zencache/issues/504). - **Enhancement**: In Logged-In User Caching, the "Yes, but DON'T maintain a separate cache for each user" option has been hidden because this particular option has the potential to create a security issue if not configured properly. If you were already using this option, it will not be hidden and it will continue to work. Otherwise, if you require this particular option you can now enable it using a filter (see [this comment](https://github.com/websharks/zencache/issues/497#issuecomment-146060440)). Props @renzms @jaswsinc. See [Issue #497](https://github.com/websharks/zencache/issues/497). - **Enhancement**: The Auto-Cache Engine now detects when the configured XML Sitemap is not valid or is unreachable and displays an appropriate notice. Props @kristineds and @jaswsinc. See [Issue #555](https://github.com/websharks/zencache/issues/555). = v151004 = - **Bug Fix**: Fixed a bug introduced in the previous release that was resulting in a "Fatal error: Using $this when not in object context" for sites running PHP 5.3. (PHP 5.4+ sites were unaffected.) Props @jaswsinc. See [Issue #581](https://github.com/websharks/zencache/issues/581). = v151002 = - **New Feature!** Cache Statistics is a completely new ZenCache Pro feature that will help site owners better understand their WordPress site cache. An easy-to-access Cache Stats menu button in the Admin Bar is accompanied by a whole new page that shows Current Cache Totals (including total number of cache files and total size of cache on the disk), Current Disk Health (including total disk capacity and total available), Current System Health (including memory usage and load average), and two beautiful Polar Area pie charts that show you both current and historical data on Cache File Counts and Cache File Sizes with a 30-Day High, Current Total, Page Cache total, and HTML Compressor total for each chart. Props to @jaswsinc. See [Issue #83](https://github.com/websharks/zencache/issues/83). - **New Feature!** It's now possible to specify which WordPress Roles/Capabilities are allowed to clear the cache from the WordPress Admin bar. A new option inside _Dashboard → ZenCache → Plugin Options → Manual Cache Clearing_ allows specifying a comma-delimited list of Roles and/or Capabilities under, "Also allow others to clear the cache from their Admin Bar?". If a user has an allowed Role/Capability, they will see the "Clear Cache" button in their Admin Bar. This feature is also compatible with WordPress Multisite Networks, allowing a Network Administrator to define which Child Site roles should allow a Child Site user to see the "Clear Cache" button for their Child Site. Props @danielmt2k @jaswsinc. See [Issue #68](https://github.com/websharks/zencache/issues/68). - **New Feature!** It's now possible to "Disable Cache Expiration If Server Load Average is High" (see _Dashboard → ZenCache → Plugin Options → Cache Expiration Time_). This allows you to provide a specific load average that should cause ZenCache to disable cache expiration and help reduce stress on the server; i.e., to avoid generating a new version of the cache while the server is very busy. Props @jaswsinc. See [Issue #347](https://github.com/websharks/zencache/issues/347). - **New Feature!** It's now possible to manually clear the CDN Cache when Static CDN Filters are enabled. Inside the Static CDN Filters options panel there's a new "Clear CDN Cache" button and there's also a new option ("Clear the CDN Cache Too?") inside _Dashboard → ZenCache → Plugin Options → Manual Cache Clearing_ that allows you to specify whether or not you'd like the CDN Cache to be cleared whenever the "Clear Cache" button is clicked (either from the Admin Bar or from inside the Plugin Options). Props @kristineds @jaswsinc. See [Issue #488](https://github.com/websharks/zencache/issues/488). - **New Feature!** When your server has the [PHP OPCache Extension](http://zencache.com/r/php-opcache/) installed, ZenCache can now be configured to also clear the PHP opcode cache whenever you clear the cache manually using the ZenCache "Clear Cache" button. See _ZenCache Options → Manual Cache Clearing → Clear the PHP OPCache Too?_ (note that this option only appears if you have the OPCache Extension installed). Props @jaswsinc. See [Issue #489](https://github.com/websharks/zencache/issues/489). - **Bug Fix**: Fixed an HTML Compressor bug related to CSS pseudo-classes where spaces between the class name and pseudo-class name were being removed when CSS was minified. Props @patdumond @jaswsinc. See [Issue #544](https://github.com/websharks/zencache/issues/544). - **Bug Fix**: Fixed an HTML Compressor bug related to `