sdk/filesystem/#filesystemdocumentdirectory
In general web browsers have no access to the local file system.
I noticed snack expo → Web does not want to work with FileSystem.documentDirectory
Whereas snack expo → Android → Tap to Play (Appetize.io) outputs something like
FileSystem.documentDirectory = file:///data\user/0/host.exp.exponent/files/ExperienceData/$user$project/
Could it not work with something like window.requestFileSystem()