Create standalone group
The behavior by default when you have baggage files linked in your source documents is to copy them to your Output folder in the corresponding group folder. Reverb creates a baggage folder inside the group folder and it copies there all your baggage files and its dependents (if you have Copy baggage file dependents -> Enabled), and also copies creates the corresponding bpair.js files containing the pairs in each baggage file to the pairs folder inside that group. Additionally, in your group index file (with format NameOfTheGroup_sx.js in the output target folder), Reverb adds the indexed words for every baggage files with its relevance.
Note: If your Output Format is Reverb 2 Standalone groups are not supported and this section does not apply.
The problem with the default behavior is that if you use the same baggage file across different groups, you’ll have it duplicated in your Output folder, because it’s going to be copied to every group folder and furthermore you are going to have duplicate results in your Search Results pointing to the different groups where that file lives.
But if you have the Create standalone group setting Enabled in your Target Settings, Reverb instead of copying to every group the corresponding baggage files, it will create an “imaginary” parallel group to the other groups that it will only contain 2 folders: baggage and pairs, containing all related with the baggage files across all groups. Also it will create an index file, with all the indexed words in each baggage file (named StandaloneGroupName_sx.js, using as StandaloneGroupName the one defined in Standalone group name) in the output target folder. Now you will have an independent index for all your baggage files and all the information related with them in the same place (a common folder).
Note: If you have this setting Enabled and the Index baggage files setting -> Enabled all the entries in the baggage files info list representing baggage files that are not in your source documents will be indexed as well. So this is a way to index files not contained in your source. Also, if you have the Index external links setting Enabled combined with this setting, Reverb will index those external links from the baggage files info list.