This issue is caused by Enfold loading some assets on some WooCommerce Admin Screens (e.g. Dashboard, Orders, Coupons) without solved dependencies.

The assets in question are:

/enfold/config-templatebuilder/avia-template-builder/assets/js/avia-tab-section.js
/enfold/config-templatebuilder/avia-template-builder/assets/js/avia-table.js
/enfold/config-templatebuilder/avia-template-builder/assets/js/avia-tab-toggle.js
/enfold/config-gutenberg/js/avia_gutenberg.js
/enfold/config-gutenberg/css/avia_gutenberg.css
/enfold/config-templatebuilder/avia-template-builder/assets/js/avia-media.js

Theese javascript and css files have the following dependencies:

avia_builder_js
avia_modal_js
avia-modal-style
avia-builder-style
avia_element_js

The problem occurs because the dependencies don’t get loaded on the WooCommerce Admin Screens. Therefore the handles are not registered.
Enfold has always loaded those assets in various places where they are not needed at all (i reported that at least two times). With version 4.2 WooCommerce introduced a script preloader which checks for dependencies.

Enfold has either to stop loading assets where they are not needed or to make sure the dependencies get loaded if an asset is needed.

As for now the only thing you can do is to switch of debug mode to get rid of the php notices. But you have to life with tons of error log entries until Enfold fixes the bug.

@neverstar just activate the classic editor plugin and all is good.

@extraeyes I don’t insult you. I tried to help. So calm down. The information provided comes from your websites sourcecode:

Debugging Info for Theme support:
Theme: Enfold
Version: 3.3.2
Installed: enfold
AviaFramework Version: 2.2
AviaBuilder Version: 0.8
ML:256-PU:44-PLA:6
WP:4.7.3
Updates: disabled

That information says your installation is out of date.

I have removed my video now. If this was a new bug I would say ‘can happen’. But this video issue is getting worse with each new version. I am tiered of debugging that problem again and again.

Local mp4 files used for background videos on color section do not work either. Ajax loader image spins forever and mejs-container shows as small grey row.

• This reply was modified 6 years, 1 month ago by mensmaximus.

This would be absolutely inappropriate. It neither describes the issue nor does it contain any props to the person who found the core reason and provided a solution. (me ;-))

Issue isolated.

tl;dr
1. Open /enfold/config-templatebuilder/avia-template-builder/php/meta-box.class.php
2. Locate function handler_wp_insert_post_data near line 223
3. Locate the code block if( ‘revision’ == $data[‘post_type’] ) { return $data; } within function handler_wp_insert_post_data
4. Add the following code block after the code block located in #3:

/*
 * Temporary fix for Enfold triggering the non catchable error -1 
 * after executing the check_ajax_referer (wordpress core function)
 * if a tribe event has a ticket attached (woocommerce product).
 *
 * @see https://kriesi.at/support/topic/error-saving-event-events-calendar-pro-event-tickets-pro/
 *
 * @todo Kriesi needs to implement a permanent fix
 */
if( $_POST['post_type'] == 'tribe_events' && $postarr['post_type'] == 'product' ) {
	$product_id = $postarr['ID'];
	$ticket_product_ids = isset( $_POST['tribe-tickets']['list']) ? array_keys($_POST['tribe-tickets']['list']) : array();
	if( in_array( $product_id, $ticket_product_ids ) ) {
		return $data;
	}
}

5. Save the file. You tribe events with attached tickets will save again.

Short description

Enfold introduced the function handler_wp_insert_post_data() in version 4.2.1. The call to check_ajax_referer() from within returns -1

Detailed description

The function handler_wp_insert_post_data() introduced in Enfold version 4.2.1 cares about Advanced Layout Builder Metaboxes attached to posts/pages. Posts/pages without ALB metaboxes are ignored. By default the posttype tribe_events does not support Enfold metaboxes and gets ignored by handler_wp_insert_post_data(). The plugin Tribe Event Tickets Plus allows to add tickets to events using WooCommerce. The posttype product used by WooCommerce supports Enfold metaboxes by default and gets handled by handler_wp_insert_post_data(). This is where the issue stems from.

Saving an event with attached ticket will trigger the WordPress core filter wp_insert_post_data two times. The first call is for the event (tribe_events). The second call is for the ticket (product). The function handler_wp_insert_post_data() is hooked into the filter wp_insert_post_data and parses both save actions. The first call is ignored because the posttype tribe_events has no ALB metaboxes attached. The second call gets processed because the posttype product has ALB metaboxes attached. But because the save action has been initiated from an event (tribe_events) the nonce needed to pass the call to check_ajax_referer() is missing. Therefore the result of check_ajax_referer() is false and because check_ajax_referer() is set to die by default ($die = true) instead of returning the result WordPress dies and returns -1.

Solution

As a quick fix you can modify the function handler_wp_insert_post_data() in class MetaBoxBuilder as described above. What it does it to check the original posttype where the save action has been invoked from (tribe_events) and the posttype passed to handler_wp_insert_post_data(). If the original posttype is tribe_events and the posttype seen in $postarr is product a second check is performed. It will test whether the ID of the product matches any of the ticket (product) IDs attached to the event. If this is true the processing of function handler_wp_insert_post_data() is aborted and the original data are returned.

Another solution might be to add ALB metaboxes to the posttype tribe_events using the filter avf_builder_boxes. However I did not test it because this won’t solve the root cause of the issue.

@kriesi

A permanent fix must work for tribe events with attached tickets regardless whether ALB metaboxes are attached or not. One way would be to introduce a new filter before calling check_ajax_referer() and to execute check_ajax_referer() conditionally. This would allow to move the logic of my fix into the config.php files of your plugin integrations.

Getting closer to it ;-)

Twenty Seventeen:
If you hook into wp_insert_post_data to dump data for debugging purpose you will see wp_insert_post_data is triggered twice if a woocommerce product (the ticket) is attached to event.

Enfold:
The second call to wp_insert_post_data for the product (the ticket) is not executed. Therefore my strong guess is the error happens during the first call to wp_insert_post_data which returns -1.

Comparing the $_POST data there are 3 main differences between Enfold and Twenty Seventeen while saving the event:

Twenty Seventeen:
[_wp_http_referer] => /wp-admin/post.php?post=7245&action=edit&message=1
[referredby] => https://domain.tld/wp-admin/post.php?post=7245&action=edit
[_wp_original_http_referer] => https://domain.tld/wp-admin/post.php?post=7245&action=edit

Enfold:
[_wp_http_referer] => /wp-admin/post.php?post=7245&action=edit
[referredby] => https://domain.tld/wp-admin/edit.php?post_type=tribe_events
[_wp_original_http_referer] => https://domain.tld/wp-admin/edit.php?post_type=tribe_events

But there are no differences in the query object (global $wp_query).

The big question:
– Does Enfold change something that Events Tickets Plus needs to save the product data
or
– Does Events Tickets Plus modify something to prevent Enfold from saving

@cnovery please update your PHP version to at least 5.6. Better to 7.1. Most hosting providers allow switching the PHP version from their customer control panel.

This is what i meant. Because I don’t use it I could not recall the name ;-)

@ruffidea yes the effect would be immediate (if the hosting provider has no delay). Maybe an other plugin now has an issue with PHP7. Can you switch to PHP 5.6?

• This reply was modified 6 years, 3 months ago by mensmaximus.

@ruffidea please update your PHP version to at least 5.6. Better to 7.1. Most hosting providers allow switching the PHP version from their customer control panel.

@yigit you would have to downgrade to PHP 5.4 to reproduce the issue. Other than stated by some participants you don’t need PHP 7.x to solve a ‘Can’t use function return value in write context’ issue. PHP 5.5 would theoretically be enough. However since 5.5 is EOL and 5.6 as well as 7.0 will be EOL end of 2018 it is recommended to upgrade PHP to 7.1.

The ‘Can’t use function return value in write context’ issue stems from the way you use empty(). Prior to PHP 5.5 only variables (strings) could be used within empty(). Starting with PHP 5.5 functions can be used. Enfold tests whether a trimmed array element is empty. Trim() is a function and therefore PHP 5.4 fails. PHP 5.4 is EOL since nearly 2.5 years. Unfortunately according to wordpress.org 25% of all WordPress installation still run on PHP 5.4 and smaller!

If I would be Christian I would disallow the theme activation if PHP is smaller than 5.6. For PHP less than 7.1 I would throw a warning notice about the upcoming end of life and suggest an update. If the top ten theme developers would form an alliance against outdated PHP versions such issues would never happen again. WordPress (the core development team) seems not brave enough to take this road.