Itch.io is migrating to a new CDN provider which will result in a change to the domain where HTML games are hosted. The effect of this change is that data saved in your browser by HTML games hosted on Itch.io will be lost when the switch over to the new domain happens some time before the end of November (no exact date provided by Itch.io yet).
This means that all settings and high scores for RetroFab simulations will also be lost when the change comes into effect :(
For those who would like to retain all their RetroFab high scores and settings, I've written a simple command line utility, RetroFab Utils, that will allow you export all your save data to a file and then import it back once the domain change is implemented on Itch.io.
This utility can also be used if you want to transfer your save data to a different browser, as well as to transfer save data to the downloadable desktop version when it's released.