That changed in version 17 with the introduction of Building Materials.
In the profile manager you now set a Building Material instead of choosing the fill pattern.
You control the fill used for the building material in the Building Material Settings.
So you will find the fit to fill option there (but only if it is a symbolic fill).
One of the forum moderators. Versions 6.5 to 25 Dell XPS- i7-6700 @ 3.4Ghz, 16GB ram, GeForce GTX 960 (2GB), Windows 10 Dell Precision 3510 - i7 6820HQ @ 2.70GHz, 16GB RAM, AMD FirePro W5130M, Windows 10