i believe that local file system (LFS) would move the web forward. I have tried the Chrome, deprecated, offering and come away with these 'requirements' ...

1. the LFS must be initiated by the browser client.
2. the client storage media must be protected
3. the LFS must not be executable.

To meet these requirements i offer these suggestions ...

1. LFS is offered with the browser or not. if the client chooses that browser they have given permission
2. LFS storage is entirely contained in the browsers folder.
3. Only ascii text shall be permitted.

I realize that this prejudices in favor of English. So?

The following should be offered as the LFS javascript interface ...

1. LFS_GET_PERMISSION() returns true or false.
2. folder = LFS_CREATE_FOLDER('name') creates or locates the folder and returns 'folder'
3. file = LFS_CREATE_FILE('name') creates or locates the file and returns 'file'
4. text = LFS_READ(file) returns the entirety of the file.
5. LFS_TRUNCATE(file) clears the file specified.
6. LFS_WRITE(file, text) appends the 'text' to the file specified

The browser may prepend folder name with the page name so as to allow multiple pages to use the LFS.

I looked at W3C for a 'suggestions' link w/o success so ... If you like it pass it on, if not forget you read it.