scribu

Custom fields are great for storing various meta data about a post. However, if you routinely need to display posts that have a certain custom field value, you should consider switching to a <a href="https://codex.wordpress.org/Custom_Taxonomies" rel="nofollow ugc">custom taxonomy</a>, which is better suited for grouping posts.
With this simple plugin, you can convert all custom fields with a certain key to terms in a certain taxonomy, while maintaining the post association.
Note: If you’re looking for the old version, see <a href="https://wordpress.org/extend/plugins/custom-query-fields/" rel="ugc">Custom Query Fields</a>
Links: <a href="http://scribu.net/wordpress/custom-field-taxonomies" rel="nofollow ugc">Plugin News</a> | <a href="http://scribu.net" rel="nofollow ugc">Author’s Site</a>

Custom Field Taxonomies

Convert custom fields to tags, categories or taxonomy terms

JS Morisset

The JSM Show Order Metadata for WooCommerce HPOS plugin displays order meta keys and unserialized values in a metabox at the bottom of the WooCommerce HPOS order and WooCommerce Subscriptions editing pages.
Note that if you’re NOT using WooCommerce HPOS (High-Performance Order Storage), available since WooCommerce v8.2, then your WooCommerce orders are post objects and you should use the <a href="https://wordpress.org/plugins/jsm-show-post-meta/" rel="ugc">JSM Show Post Metadata</a> plugin instead.
There are no plugin settings – simply install and activate the plugin.
<h4>Available Filters for Developers</h4>
Filter the order meta shown in the metabox:
<pre><code>'jsmsom_metabox_post_types' ( array $post_types )
</code></pre>
Array of supported HPOS post types (i.e. ‘woocommerce_page_wc-orders’ and ‘woocommerce_page_wc-orders–shop_subscription’).
<pre><code>'jsmsom_metabox_table_metadata' ( array $metadata, $order_obj )
</code></pre>
Array of regular expressions to exclude meta keys:
<pre><code>'jsmsom_metabox_table_exclude_keys' ( array $exclude_keys, $order_obj )
</code></pre>
Capability required to show order meta:
<pre><code>'jsmsom_show_metabox_capability' ( 'manage_options', $order_obj )
</code></pre>
Capability required to delete order meta:
<pre><code>'jsmsom_delete_meta_capability' ( 'manage_options', $order_obj )
</code></pre>
Icon for the delete order meta button:
<pre><code>'jsmsom_delete_meta_icon_class' ( 'dashicons dashicons-table-row-delete' )
</code></pre>
<h4>Related Plugins</h4>
<ul>
<li><a href="https://wordpress.org/plugins/jsm-show-comment-meta/" rel="ugc">JSM Show Comment Metadata</a></li>
<li><a href="https://wordpress.org/plugins/jsm-show-order-meta/" rel="ugc">JSM Show Order Metadata for WooCommerce HPOS</a></li>
<li><a href="https://wordpress.org/plugins/jsm-show-post-meta/" rel="ugc">JSM Show Post Metadata</a></li>
<li><a href="https://wordpress.org/plugins/jsm-show-term-meta/" rel="ugc">JSM Show Term Metadata</a></li>
<li><a href="https://wordpress.org/plugins/jsm-show-user-meta/" rel="ugc">JSM Show User Metadata</a></li>
<li><a href="https://wordpress.org/plugins/jsm-show-registered-shortcodes/" rel="ugc">JSM Show Registered Shortcodes</a></li>
</ul>

JSM Show Order Metadata for WooCommerce HPOS

Must need for Developer

Show WooCommerce order metadata in a metabox when editing HPOS orders - a great tool for debugging issues with HPOS order metadata.

Custom Field Taxonomies vs JSM Show Order Metadata for WooCommerce HPOS