Coda uses your browser's local storage to save your changes before they are sent to our servers. This helps ensure that your changes aren't lost if you lose network connectivity or close your browser. If you've been offline, when your browser reconnects, any local changes are synchronized with our servers.
However, your browser places limitations on how much space Coda (or any other web app) can use, and it's usually smaller than the total free space on your hard drive. When that happens, you'll see a message like this:
To continue writing and collaborating, you'll need to free up space on your computer, such as by clearing your cache, removing files or deleting old applications. Once more space is available to Coda, the message will disappear automatically and your changes will be saved.
If you cannot free space at this time, we recommend copying and saving any changes you've made since the error message showed up out of Coda to avoid losing your work.