Story: As a PM/UX Designer we want to know if a new feature performs better/worse/different than an old one.
Context: To properly evaluate the impact, we need random assignment
- Randomly assign to the old-algorithm or the new-algorithm group in an arbitrary split (e.g. 50/50%)
- Save the assignment group in a cookie
See also T170392: Create gadget that enables the use of the elastic search backend for the entity selector for an opt-in / opt-out variant.