What is the correct syntax for the 'Predefined expressions' feature of the Raster Calculator of QGIS 3.14? How one can replace layer names with variables in the expression being saved (so they can be selected from dropdowns later, just like in predefined NDVI formula)? Is adding some other variables possible?
I mean the calculator which can be found in Processing Toolbox > Raster analisys > Raster calculator, not the one from the 'Raster' menu > Raster Calculator. (By the way, why there are two raster calculators?)