We need an API for storing origin-specific resources in a non-permanent way. The API should let consumers read and write data to a specific file-name for a given origin. Once we hit a total limit of X MB for all origins, we should use some heuristic to figure out which origin we should toss out the data for, and do so automatically without the API consumer having to worry. We might also want to enable API consumers to "lock" the data for an origin so that we don't throw out any data while the user is on a given site. For example we could do so when a site opens an IDB database, and unlock when all IDB databases for a given site is closed. Most likely we should build this API on top of SQLite's virtual file system. That way it'll be easy to get our SQLite backends for IndexedDB and localStorage to use this API and get the behavior we want.

Is this what FileManager et al are aiming at, or is that something entirely different, or is that what the functionality for this bug is supposed to be built on?

https://bugzilla.mozilla.org/show_bug.cgi?id=1472046 Move all DOM bugs that haven’t been updated in more than 3 years and has no one currently assigned to P5. If you have questions, please contact :mdaly.