John Blackbourn – @johnbillion

Member Since: December 7th, 2005
Location: Tonbridge, UK; and Torino, Italy
Website: johnblackbourn.com
Job Title: Senior WordPress Engineer
Employer: Human Made Ltd
Find me on:

Bio

I’m one of the team of WordPress core developers. I was the release lead for WordPress 4.1. I work as an engineer at Human Made.

Previously I’ve worked at Code For The People and WordPress.com VIP.

Find me on GitHub and Bleeter.

Contributions Sponsored

John Blackbourn contributes 8 hours per week to the following teams: CLI, Core, Documentation.

Contribution History

Accessibility Contributor
Accessibility Contributor
bbPress Contributor
bbPress Contributor
Core Contributor
Core Contributor
Core Team
Core Team
Documentation Contributor
Documentation Contributor
Meetup Organizer
Meetup Organizer
Meta Contributor
Meta Contributor
Translation Contributor
Translation Contributor
WordCamp Speaker
WordCamp Speaker
Plugin Developer
Plugin Developer

Activity
Plugins
Favorites

Posted a reply to Add Cron and Execution Time, on the site WordPress.org Forums:
What URL do you get redirected to when you save the PHP cron event?

24 hours ago
Created a new ticket, #48650, in Core Trac:
Clarify function descriptions for get_gmt_from_date() and ...

2 days ago
Closed ticket #48568, in Core Trac:
$ not defined on edit screen anymore

2 days ago
Posted a reply to Switch To link destination, on the site WordPress.org Forums:
Yeah you can add a redirect_to parameter to the link and it'll redirect the user…

2 days ago
Posted a reply to Could not switch users – no caching, default environment, on the site WordPress.org Forums:
Also check to see if you've got any mu-plugins or dropin plugins in place, they…

2 days ago
Posted a reply to Could not switch users – no caching, default environment, on the site WordPress.org Forums:
Sorry you're having trouble. I know it sounds basic but clearing all your cookies for…

2 days ago
Committed [46729] to Core Trac:
Docs: Correct some invalid hook docblocks. See #48303

4 days ago
Closed ticket #19647, in Core Trac:
Use add_node() instead of add_menu() in core

1 week ago
Committed [46678] to Core Trac:
Toolbar: Un-deprecate the `WP_Admin_Bar::add_menu()` method. This is ...

1 week ago
Reopened ticket #19647, in Core Trac:
Use add_node() instead of add_menu() in core

1 week ago
Committed [46673] to Core Trac:
Post WordPress 5.3 RC4 version bump.

2 weeks ago
Committed [46672] to Core Trac:
WordPress 5.3 RC4.

2 weeks ago
Committed [46670] to Core Trac:
REST API: Use explicit dates in a post ordering test to avoid ...

2 weeks ago
Committed [46666] to Core Trac:
Block Editor: Bug fixes targeted for WordPress 5.3 RC4. Merges ...

2 weeks ago
Committed [2186495] to Plugins Trac:
Tagging 1.5.3

2 weeks ago
Committed [2186494] to Plugins Trac:
Committing 1.5.3 to trunk

2 weeks ago
Posted a reply to Recording the admin user on woocommerce orders?, on the site WordPress.org Forums:
Thanks for the question! User Switching stores the old user ID in the switched_from_id property…

2 weeks ago
Posted a reply to 502 error, on the site WordPress.org Forums:
By the way, if you look at the error log on your site, you should…

2 weeks ago
Posted a reply to 502 error, on the site WordPress.org Forums:
Thanks for the report. I also see this issue myself occasionally but I've not pinned…

2 weeks ago
Posted a reply to Uncaught error in php_errors.php, on the site WordPress.org Forums:
This is a problem with the woo-postnl plugin. Query Monitor is just reporting the error…

2 weeks ago
Posted a reply to WP Cron failed to complete, on the site WordPress.org Forums:
That page URL isn't from this plugin. Sorry!

3 weeks ago
Posted a reply to WP Cron failed to complete, on the site WordPress.org Forums:
It doesn't show success and failure. Are you sure you have the correct plugin?

3 weeks ago
Posted a reply to WP Cron failed to complete, on the site WordPress.org Forums:
Sorry that you're having a problem with your cron events. This doesn't sound like it's…

3 weeks ago
Created a new ticket, #4783, in Meta Trac:
Invalid hooks listed in Code Reference

3 weeks ago
Posted a reply to Missing Dependencies wp-auth-check + autosave, on the site WordPress.org Forums:
Unfortunately I'm unable to help debug individual issues that QM surfaces. It would be a…

1 month ago
Posted a reply to Crontab doesn’t work, on the site WordPress.org Forums:
Sorry you're having problems. This is how the cron system in WordPress works, it's not…

1 month ago
Committed [2170263] to Plugins Trac:
Tagging 3.4.0

1 month ago
Committed [2170262] to Plugins Trac:
Committing 3.4.0 to trunk

1 month ago
Posted a reply to Compatbility with WooCommerce Wholesale Prices Premium Plugin, on the site WordPress.org Forums:
I'm unable to support paid plugins. Your best bet is to get in contact with…

1 month ago
Posted a reply to Cart content is copied when switching users, on the site WordPress.org Forums:
Are you using WooCommerce 3.6 or later? This is an issue with earlier versions of…

1 month ago
Posted a reply to See Admin Features in User View, on the site WordPress.org Forums:
Nope, not unless you create a user role that has just the capabilities that allow…

2 months ago
Posted a reply to Monitor the Ajax request, on the site WordPress.org Forums:
The short answer is no, there's not currently a way to do this but it's…

2 months ago
Posted a reply to QM finish vs page finish, on the site WordPress.org Forums:
The short answer is yes, and this may mean there's probably a network connectivity issue…

2 months ago
Posted a reply to How to Switch Back from WooCommerce Customer account?, on the site WordPress.org Forums:
In addition to the admin toolbar there's a Switch Back button in a few places:…

2 months ago
Wrote a comment on the post New Block APIs in WordPress 5.3, on the site Make WordPress Core:
`register_block_style()` is neat. When the style_handle argument is passed, does the style get automatically enqueued…

2 months ago
Posted a reply to Slow Queries on wp_options, on the site WordPress.org Forums:
This is something you'll need to speak with your web host about. A transient update…

2 months ago
Posted a reply to Cron action callback not executing, on the site WordPress.org Forums:
I've seen this a few times but I've never been able to track down the…

2 months ago
Posted a reply to PHP Warning: Use of undefined constant DB_USER, on the site WordPress.org Forums:
This sounds like something's gone wrong with your site configuration. DB_USER is a standard constant…

2 months ago
Posted a reply to Argument 1 passed to QueryMonitor::filter_plugin_action_links() must be array, on the site WordPress.org Forums:
Thanks for the report. This sounds like another plugin on your site is incorrectly filtering…

2 months ago
Posted a reply to Unable to View Query Monitor on Frontend, on the site WordPress.org Forums:
If you view the source code of the page, can you see any of QM's…

2 months ago
Posted a reply to cache issue, on the site WordPress.org Forums:
Sorry you're having problems. You're probably better off asking the author of the caching plugin.…

2 months ago
Posted a reply to User Switching fails after second time Switching to a user, on the site WordPress.org Forums:
User Switching does support nested switching (in case you were wondering), so this should work…

2 months ago
Posted a reply to The link you followed has expired, on the site WordPress.org Forums:
Can you clear all your cookies and try again?

2 months ago
Posted a reply to Required to login when switching, on the site WordPress.org Forums:
Can you clear all your cookies and try again? If that doesn't work, what exactly…

2 months ago
Posted a reply to PHP Fatal Error – Multiple Cron Events, on the site WordPress.org Forums:
I'd you can't edit this event then something has gone very wrong with the storage…

2 months ago
Posted a reply to PHP Fatal Error – Multiple Cron Events, on the site WordPress.org Forums:
This error means you have a fatal error occurring in the PHP code in your…

2 months ago
Posted a reply to View query attachments with query monitor?, on the site WordPress.org Forums:
QM doesn't currently expose all the same debugging information for Ajax calls as for regular…

2 months ago
Posted a reply to Include User Switching Link Outside users.php, on the site WordPress.org Forums:
Yeah you can do this with the following code: $link = user_switching::maybe_switch_url( $user ) where…

2 months ago
Posted a reply to Deny Switching cap for roles, on the site WordPress.org Forums:
Link to the tests for this: https://github.com/johnbillion/user-switching/blob/e800a11f42ab94e2692b9d937b244aef37dd2e26/tests/test-caps.php#L112-L156

2 months ago
Posted a reply to Deny Switching cap for roles, on the site WordPress.org Forums:
Yep you need to set the $grant parameter to false for the capability. Removing the…

2 months ago