It is a non-standard post attribute that could come from the ‘post custom fields feature’ or other plugins that extend the post’s meta-data. The most known such plugins are custom fields providers, e.g. Meta Box – WordPress Custom Fields Framework.
As a result, any custom fields have an ID and vale. So, these fields should be added as separate body attribute with name equals to that ID.
Note. All custom attributes are interpreted by default as HTML. To interpret it as a simple text it should be marked by ‘Raw’ style as in the sample.
In-place edit mode#
In in-place edit mode, these attributes are set in the post’s meta-data editors with the same ID.
Note: ‘post custom fields’ currently is not supported. If it is needed, please, write to us.
In direct\batch mode, these attributes are stored in the post’s meta-data with the same ID.
Note: Common practice is to prefix ID with ‘_’ to hide it from ‘post custom fields feature’.