Sphinx search box function not really working

[maxnoe]

Reported by @Tobychev via slack: searching for "cuts" or "cut" or even the exact method name "calculate_percentile_cuts" does not turn up any results in the sphinx docs

[HealthyPear]

This is weird. Usually you don't need any specific configuration to make this work.

I saw that we are using sphinx 6 from the CI and in the original repository I couldn't find any open or recently closed issue about this.