I don’t think you’ll find it. Mayonnaise has a mechanism of lipid oxidation catalysed by iron ions present in egg yolks. Most mass produced mayonnaise contains EDTA to chelate metal ions and slow down lipid peroxidation. Lipid oxidation is also known as rancidity.

You can test this yourself by leaving a metal utensil in some mayo for a couple hours. It should turn black from a redox reaction

Otherwise I’d have to install a gui

If you’re already using an esp32 why not just get a simple ultrasonic sensor and measure flow on an indoor inlet pipe? You may need to know the pressure (probably 1.7 kPa) and temperature but that should be possible to calibrate against your meter readings

Then your project just becomes a simple pipe clamp that can be indoors

This just seems to be detecting if the browser is Firefox. The function is even named isGecko which is Mozilla’s browser engine used by Firefox. Edge, IE (Trident) don’t return true from isGecko

Unless I’m missing something I don’t see where the delay is added