...Just to add to this point, as mentioned here:
"Savegames are not saved in the cache. The browser cache is a very much temporary storage that is used to save things like images on web pages without having to re-download them every time, and it's regularly cleared. Savegames don't go there (luckily), they are stored in either WebStorage or IndexedDB, which are permanent storages and are not affected by the user clearing their cache."
This was why ~I wanted to use the save game function, but on both Safari and Chrome, once I clear the cache, my saved data is gone