Filebrowser v2 Explanation

[ferndot]

The next version of the Firetext file browser will include multiple key improvements:

• It will be a module, enabling better encapsulation ([File browser] Make module #181).
• It will support multiple SD Cards (Support multiple sd cards #170).
• It will follow the file system's directory structure, instead of showing all files in a meta list ([File browser] Keep directory structure #174).
• It will have more features, such as renaming and search (File action: rename doc #119, Implement search #155).

Note: it is best to wait to implement this until IO v2 has landed (#190).