Users can now save their projects within a PostgreSQL database. Project can be saved in menu Projects > Save To > PostgreSQL and loaded using menu Projects > Load From > PostgreSQL. Projects saved in database can be loaded also through the browser dock (projects show up under the schema where they were saved, together with other layers).
Saving/loading QGIS projects must be explicitly enabled in PostgreSQL connection settings: there is a new option "Allow saving/loading QGIS projects in the database" which is disabled by default.
New API has been introduced that allows creation of custom project storage implementations (may be used by plugins). Related QEP: https://github.com/qgis/QGIS-Enhancement-Proposals/issues/118
This feature was funded by Arpa Piemonte (Dipartimento Tematico Geologia e Dissesto) within ERIKUS project
This feature was developed by Martin Dobias, Peter Petrik (Lutra Consulting) and Faunalia