The Remix tool is a companion to the older Rebuild tool. Both tools attempt to find a new shape for a section of a protein by comparing three-segment "fragments" similar portions of existing proteins. A 2016 Foldit blog post describes the differences between Remix and Rebuild.
The Remix tool may assist players in creating solutions with Ideal Loops.
Compared to the Rebuild tool, the Remix tool has better support in the Folder user interface. For a given selection of segments, the tool may propose a number of possible Remix solutions. The player can review the solutions one-by-one. Solutions which look promising can be saved in quicksave slots for further analysis.
The Remix function in the Foldit Lua interface v2 similarly returns its results in quicksave slots.