De-registering heartbeat script causes meta boxes to become unresponsive

[wycks]

Using

wp_deregister_script('heartbeat');

Causes the metabox fields under the default editor to not close on click and they are not draggable. Tested on WordPress 4.0 twenty-twelve and several other themes.

Steps to reproduce.

1. Call wp_deregister_script('heartbeat'); on init.
2. Go to any post/page/cpt and try to close/open or drag a meta box (excerpt, revision, discussion, comments, etc).

[azaozz]

Happens because post.js (containing most of the JS for the Add/Edit Post screen) requires heartbeat.js. If the latter doesn't exist, the former is not loaded.

We probably can change that requirement, however heartbeat is needed for autosave, auth-check, post locks, etc. Deregistering it will disable all of them. If the purpose is to reduce AJAX requests, opened #29779 for a better way.

Thinking this should be 'wontfix' in favor of #29779.

[wycks]

It's a bit of an odd situation when these components are coupled together, one would not expect the heartbeat to effect elements not directly related to heartbeat. We recently just reduced requests by changing the timer instead of deregistering the script, I just found it odd it would cause that bug. Feel free to close.

[azaozz]

Thinking more about this: we can "decouple" heartbeat from other scripts that can work without it. In practice only autosave.js requires it.

[azaozz]

In 30008.patch:

• Remove 'heartbeat' dependency for post.js and inline-edit-post.js. They can function correctly (with reduced functionality) when heartbeat is not loaded.
• Fix dependencies for autosave.js.

[SergeyBiryukov]

+1 for 30008.patch​, I saw a request on support forums today similar to this ticket.

[azaozz]

In 29989:

Script-loader: remove 'heartbeat' dependency for post.js and inline-edit-post.js, fix dependencies for autosave.js. Fixes #30008