Controls the folder, file, and blocks that are displayed in the Libraries tab of the Blocks palette.
| Type: | String |
| Saved in: | Registry |
| Initial value: | None |
Valid values are folder paths, full file names that include the path, file name, and extension of an existing file, or "." for none. When set to none, the last-used file or folder is retained the next time the palette is opened and persists across sessions.