OpenCola reminds me of the work I did making my own Club Mate clone, including a delicious sugar free Club Mate clone.
The one thing I never cracked was Club Mate Winter Edition.
Maybe this is worth turning into a project?
@serge RevSpace folks did something similar with Alklanet: https://revspace.nl/RevKlanet
@joepie91
Oh yeah I've done similar with fountain pen flush. Mine is ridiculously cheap.
In all honesty, with how little I use it, it's probably not worth it, but they charge a fortune for pen flush.