As more people use content types and entries we are seeing increasingly complex content being modelled. This has lead to some content types having large numbers of fields.
As the number of fields increases this adds pressure to search. As we index entries for search each field is mapped to an index and made available for search. Each of these mappings has to be processed and takes time.
Composers are typically used by editors to create body in content types such as blogs, it's not unusual to see 30+ fields used for some body content, take into consideration that some of these may be components which in turn have multiple fields and you can see how we can get an explosion of fields.
Ideally we need to keep this number to under 1000, the way we have achieved this is to change the way we map composers in search. Composers are now mapped as a flattened type which means you can still use certian operators but without the need to map each field.
When making this change we looked at a large number of searches being carried out and there were no cases where searches were targetting individual fields within a composer for search. In most cases the intention is to search all the content of a composer as part of a site search, you can now do this using the searchContent field which contains content from all fields in an entry including composer content.
In v14 you can still search the entire composer field using the following search operators: