Is it possible to save expression, so one doesn't have to retype?
1 Answer
This Feature has been introduced with QGIS 3.14, see: https://www.qgis.org/de/site/forusers/visualchangelog314/index.html#feature-add-ability-to-edit-import-and-export-user-expressions
Once saved, you will find them in "user expressions":
In older versions, you can only use the ones in "recent" as already mentioned by @Erik: