Undefined index: separator-gp – severe conflicts with other plugins

Notice: Undefined index: separator-gp in …/wp-admin/includes/menu.php on line 298

This popped up about a year ago and was attributed to an issue in the network admin on multi-site installs. Wrongly, it seems: I’m seeing this notice on a single-site version.

The real problem is that it introduces bad conflicts with another plugin – Advanced Custom Fields. I’m getting a lot of warnings like this:

Warning: Cannot modify header information – headers already sent by (output started at …/wp-admin/includes/menu.php:298) in …/wp-includes/pluggable.php on line 1228

…and I can’t access a number of admin views. It also completely messes up the export function in Advanced Custom Fields – presumably the consequence of some chain of issues.

For the time being, I’m using an mu-plugin that simply unhooks your custom_menu_order function:

remove_filter( 'menu_order', 'custom_menu_order' );

…which bumps GigPress all the way down the menu order, without a separator. Everything else seems to work as expected, within GigPress as well as Advanced Custom Fields.

This works for now, but of course it would be nice to see this fixed, and to see GigPress up in the group with Posts, Pages etc. I don’t have the time or expertise to make a suggestion for changes in custom_menu_order, sorry – perhaps you can replicate this and/or see what’s going on.

Thanks

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