I tested in Firefox on Linux. It works well except:
1. Copy and paste does not work and this could be bad for basically every editing task (programming etc).
2. The screen freezes sometimes and keypresses don't appear. Usually pressing backspace unfreezes the screen. Firefox about:performance doesn't show any CPU usage in the tab. Linux's htop (on my machine) doesn't show anything strange with Firefox.
And a question: I saw that new files persist after closing the tab and opening it again. I didn't investigate my localstorage etc with Developer Tools. Did you use that or some other browser feature? How truly persistent are those files?
1. Support for traditional copy/paste shortcuts is problematic, since Ctrl-C is interpreted as the SIGINT signal. Copying via the mouse menu should work. Pasting is supported via Ctrl+Shift+V.
To answer you question: filesystem chunks are cached/persisted using a local IndexedDB. It provides a fairly strong level of persistence, although the user can wipe it out of course.
Copy&paste via menu works (I didn't think about it) and Ctrl+Shift+V works too. Ctrl+Shift+C opens Firefox's Developer Tools. It's difficult to find a reasonable shortcut.
1. Copy and paste does not work and this could be bad for basically every editing task (programming etc).
2. The screen freezes sometimes and keypresses don't appear. Usually pressing backspace unfreezes the screen. Firefox about:performance doesn't show any CPU usage in the tab. Linux's htop (on my machine) doesn't show anything strange with Firefox.
And a question: I saw that new files persist after closing the tab and opening it again. I didn't investigate my localstorage etc with Developer Tools. Did you use that or some other browser feature? How truly persistent are those files?