Setting a Default Referance Language is useful when working with localization files that contain string IDs/keys. It can be set by the project owner and administrators, on a project level, for all contributors to see above the string IDs.
How to set a Default Reference Language
1) Add your software's source language to your POEditor localization project using the Add Language button in the project page.
2) Use the Import terms button in the project page to bring from the localization file to the localization project the terms (the string IDs) and also, in the language added at step 1, the strings in your source language.
If this is your first import, the language where you uploaded the translations should be automatically set as DRL.
To change the DRL, go to Project Settings, click on Edit Project Details, select your desired Default Reference Language and click on Save project details.
Note: Contributors can choose any other language in the project as Reference Language, just for themselves, if they are granted Read Access to All Languages in Project Settings, by the project owner or by an admin.