1. Added GUI friend function
2. Added the option of whether to close the menu after clicking on the custom menu
3. Added fly command function
4. Added @Player function
5. Added support for line breaks in email text content
6. Added color chat function
7. Added tpback command (can cross the world)
8. Added welcome for new players
9. Added the function of OP command to reset player login password
10. Optimize the secure location search for random teleportation, prohibit the use of random teleportation in the hell and the end
11. Fixed the issue that the sidebar would not refresh after reading new emails
12. Modified the price display of the custom menu, 0 or not set will not display the price
13. Fixed the problem that no spaces can be used to send all emails
14. Fixed the problem that the OP command cannot be used in the custom menu