4. Advanced Usage

4.1. Regular Expressions

4.2. Patterns

4.2.1. Pattern Modifier

4.2.2. Complex Patterns

4.2.3. Searching by Date

4.3. Using Tags

4.4. Using Hooks

4.4.1. Message Matching in Hooks

4.5. External Address Queries

4.6. Mailbox Formats

4.7. Mailbox Shortcuts

4.8. Handling Mailing Lists

4.9. Editing threads

4.9.1. Linking threads

4.9.2. Breaking threads

4.10. Delivery Status Notification (DSN) Support

4.11. POP3 Support (OPTIONAL)

4.12. IMAP Support (OPTIONAL)

4.12.1. The Folder Browser

4.12.2. Authentication

4.13. Managing multiple IMAP/POP accounts (OPTIONAL)

4.14. Start a WWW Browser on URLs (EXTERNAL)

4.15. Compressed folders Support (OPTIONAL)

4.15.1. Open a compressed mailbox for reading

4.15.2. Write a compressed mailbox

4.15.3. Append a message to a compressed mailbox

4.15.4. Encrypted folders