John Blackbourn – @johnbillion

Member Since: December 7th, 2005
Location: Tonbridge, UK; and Torino, Italy
Website: johnblackbourn.com
GitHub: johnbillion
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 and 4.9.1. I work as an engineer at Human Made.

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

Contributions Sponsored

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

Contribution History

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

Activity
Plugins
Favorites
Translations

Posted a reply to User Switching Plugin Issue with Banhammer, on the site WordPress.org Forums:
Banhammer is returning an invalid value from its removable_query_args filter. See https://developer.wordpress.org/reference/hooks/removable_query_args/. null is not…

39 mins ago
Posted a reply to User Switching Plugin Issue with Banhammer, on the site WordPress.org Forums:
This means Banhammer is returning an invalid value from its removable_query_args filter. See https://developer.wordpress.org/reference/hooks/removable_query_args/. null…

44 mins ago
Posted a reply to PHP Error showing up that isnt there, on the site WordPress.org Forums:
The Ajax errors you'll need to report to the author of whichever plugin is causing…

12 hours ago
Posted a reply to PHP Error showing up that isnt there, on the site WordPress.org Forums:
If your server isn't set to 0 then this means something changed it at runtime.…

13 hours ago
Posted a reply to Switch user link in PHP file, on the site WordPress.org Forums:
Yep. https://wordpress.org/support/topic/include-user-switching-link-outside-users-php/

20 hours ago
Closed ticket #39111, in Core Trac:
Don't output the adjacent posts rel link by default

3 days ago
Committed [48966] to Core Trac:
Posts, Post Types: Don't output the adjacent posts `rel` link by ...

3 days ago
Posted a reply to How to see the Total number of request to the database in the last 24 hours?, on the site WordPress.org Forums:
Nope sorry, QM only shows data for the current request. You'll need to enable a…

4 days ago
Posted a reply to Possible to tell who is impersonating a user?, on the site WordPress.org Forums:
Yep you can get this from the current_user_switched() function, which returns the WP_User object of…

5 days ago
Posted a reply to Uncaught SyntaxError: Unexpected token ‘<', on the site WordPress.org Forums:
This probably means you have an error on your site that you need to fix.…

5 days ago
Posted a reply to Use of undefined constant QM_HIDE_SELF, on the site WordPress.org Forums:
Thanks for letting me know. That plugin has caused similar problems in the past. I…

6 days ago
Posted a reply to WP Config Panel doesn’t workwhen QM is Active, on the site WordPress.org Forums:
What's "WP Config Panel"? Do you see any errors in your browser developer console? Do…

6 days ago
Posted a reply to Error Message or Event Completed?, on the site WordPress.org Forums:
That's a bit of a mystery error. It indicates a network problem with your site.…

1 week ago
Posted a reply to Error Message or Event Completed?, on the site WordPress.org Forums:
This means the event failed to run. If the event has missed its time by…

1 week ago
Committed [48941] to Core Trac:
Docs: Various docblock corrections and improvements. See #50768

1 week ago
Posted a reply to Doesn’t Switch, on the site WordPress.org Forums:
Did you make any other changes to your website? Did your web host install or…

1 week ago
Closed ticket #22726, in Core Trac:
Move 'Insert from URL' tab into the 'Insert Media' tab

2 weeks ago
Closed ticket #47519, in Core Trac:
Introduce a vertically compact view for the Revisions screen

2 weeks ago
Closed ticket #42092, in Core Trac:
Autosave immediately before a full save inserts a revision with no changes

2 weeks ago
Closed ticket #42033, in Core Trac:
Allow automatic installation and updates for drop-in plugins

2 weeks ago
Closed ticket #38780, in Core Trac:
Thumbnail images should be cropped from the centre top

2 weeks ago
Closed ticket #27669, in Core Trac:
Stale `db_version` value after update with external object cache

2 weeks ago
Closed ticket #50744, in Core Trac:
Add the WordPress-Docs standard to the PHPCS configuration

2 weeks ago
Posted a reply to Cant see shop user, on the site WordPress.org Forums:
You'll need to ask WooCommerce support about this.

2 weeks ago
Posted a reply to Not visible on front end when logged out and when you’ve disabled dashicons, on the site WordPress.org Forums:
Thanks for the message. I'm not sure how Permatters prevents assets from loading, it may…

2 weeks ago
Posted a reply to Critical error which leads to user getting deleted (and content), on the site WordPress.org Forums:
Thanks for letting me know.

2 weeks ago
Posted a reply to PHP warnings that will throw an error in future PHP versions, on the site WordPress.org Forums:
When does this error occur please? By default these constants are not used until after…

2 weeks ago
Posted a reply to weekly cron questions, on the site WordPress.org Forums:
Thanks for the recording. That means there's a bit of a mystery error occurring when…

2 weeks ago
Posted a reply to Run now button duplicate job with 01-01-1970 date, on the site WordPress.org Forums:
@fnorte Can you check the Tools -> Site Health screen and see if there's a…

2 weeks ago
Posted a reply to weekly cron questions, on the site WordPress.org Forums:
You can click Edit next to the event, and from there you can set the…

2 weeks ago
Posted a reply to Critical error which leads to user getting deleted (and content), on the site WordPress.org Forums:
Sorry but User Switching can't delete anything, this plugin just switches the user account and…

2 weeks ago
Posted a reply to cURL error 6: Could not resolve host, on the site WordPress.org Forums:
I'm sorry I'm unable to help debug individual issues that WP Crontrol alerts you about,…

2 weeks ago
Posted a reply to [PHP ERROR] Report.., on the site WordPress.org Forums:
Can you provide some more info? A list of errors on its own isn't useful.

3 weeks ago
Posted a reply to Error with Cache_File.php, on the site WordPress.org Forums:
You should contact the developer of the plugin for advice. Query Monitor tells you about…

3 weeks ago
Posted a reply to Use of undefined constant QM_HIDE_SELF, on the site WordPress.org Forums:
Where does this error display please? Are you using any add-on plugins for Query Monitor?

3 weeks ago
Wrote a comment on the post Proposal: Dropping support for old PHP versions via a fixed schedule, on the site Make WordPress Core:
Thanks for this post Juliette, and thanks Matt for discussing the issue with her. I…

3 weeks ago
Posted a reply to PHP Parse error: syntax error in wp-crontrol.php, on the site WordPress.org Forums:
Correct but the syntax error is coming from code that's been added by a user…

3 weeks ago
Posted a reply to PHP Parse error: syntax error in wp-crontrol.php, on the site WordPress.org Forums:
This is caused by a syntax error in one of your PHP Cron events.

3 weeks ago
Posted a reply to QM 3.6.4 and WP 5.5 compatybility, on the site WordPress.org Forums:
Possibly yes. It's definitely not a file that exists in WordPress by default.

3 weeks ago
Posted a reply to Link Specific Accounts, on the site WordPress.org Forums:
This is possible but you'll need to be familiar with the user roles and capabilities…

3 weeks ago
Posted a reply to QM 3.6.4 and WP 5.5 compatybility, on the site WordPress.org Forums:
@rex2020 Also there's no such file as wp-includes/init.php, I suggest that you run a virus…

3 weeks ago
Posted a reply to QM 3.6.4 and WP 5.5 compatybility, on the site WordPress.org Forums:
@rex2020 This is correct. Previous versions of Query Monitor didn't report some types of error,…

3 weeks ago
Posted a reply to QM 3.6.4 and WP 5.5 compatybility, on the site WordPress.org Forums:
Thanks for the update.

3 weeks ago
Committed [2366559] to Plugins Trac:
Updating readme/assets from GitHub

3 weeks ago
Posted a reply to QM 3.6.4 and WP 5.5 compatybility, on the site WordPress.org Forums:
This could be related to jQuery changes in WordPress 5.5. The cause is likely to…

3 weeks ago
Posted a reply to WooCommerce Analytics > Revenue tab not loading, on the site WordPress.org Forums:
Fixed in 3.6.4. See https://wordpress.org/support/topic/compatablity-problems-with-yoast/#post-13288380 for details.

3 weeks ago
Committed [2365946] to Plugins Trac:
Update to version 3.6.4 from GitHub

3 weeks ago
Posted a reply to Uncaught Error: Call to a member function get_component() on null, on the site WordPress.org Forums:
Fixed in 3.6.4. See https://wordpress.org/support/topic/compatablity-problems-with-yoast/#post-13288380 for details.

3 weeks ago
Posted a reply to Compatablity problems with Yoast, on the site WordPress.org Forums:
Ironically this error was caused by the extra error handling I introduced in 3.6.2 so…

3 weeks ago
Posted a reply to Uncaught Error: Call to a member function get_component() on null, on the site WordPress.org Forums:
Thanks for the report. I'll check this out straight away.

3 weeks ago