If you use the FontLoader element several times with the same font, memory usage increases notably.

For example create a component:

1. PrimaryText.qml
   Text {
   FontLoader { id: myfont; source: "/fonts/myfont.ttf"}

   font.family: myfont.name
   font.pixelSize: 26
   }

Then use that component as a replacement for the Text element. Each time it's used, memory consumption increases. Tested with top on Linux.