MailboxGUI Package (COD Support), Letter, and Money Mailbox sending GUI interface System
MailboxGUI 5.1.0 Changelog
MailboxGUI 5.1.0 is a major stable update that adds Book Letters, expanded COD item-currency support, API 5.1.0 payloads, improved admin inbox tools, network-mode validation, and Paper/Purpur 26.2.x compatibility.
Important Notes
- MailboxGUI 5.1.0 is required for Paper/Purpur 26.2.x compatibility.
- MailboxGUI 5.0.1 and older do not support 26.2.x sign updating correctly.
- MailboxGUI-DiscBridge users should update to MailboxGUI-DiscBridge 1.1.0 or newer for full 5.1.0 notification support.
- Dynmap markers are not supported on 26.1.x or 26.2.x, but core MailboxGUI features still work normally.
- Back up your server and
/plugins/MailboxGUI/before updating.
Compatibility
Supported server versions:
Spigot/Paper/Purpur 1.18.2 through 1.21.11
Spigot/Paper/Purpur 26.1.x
Spigot/Paper/Purpur 26.2.x
New: Book Letters
MailboxGUI now supports Book Letters alongside Classic Paper Letters.
Book Letter features include:
- Real Book and Quill writing flow
- Protected temporary draft book
- Sign-and-close sending
- Safe cancel support using
cancel - Logout cleanup protection
- Original hotbar item restoration
- Reply links for player-sent inbox Book Letters
- Back to Inbox links while reading from the inbox
- No reply links for admin/server/API Book Letters
- Inbox-only clickable actions removed when a Book Letter is taken from the inbox
Player flow:
/mailbox
Send Mail
Letter
Book Letter
Select Recipient
Admin flow:
/mailbox admin tools
Send Mail
Letter
Book Letter
New Admin Book Letter Command
Added:
/mba sla <recipient[,recipient2]|allplayers|onlineplayers> '<message>' --title <title> [--from <sender>] [--delay <seconds>]
Examples:
/mba sla Rismr1 'Read page two for the message.' --title Welcome --from ICServices
/mba sla allplayers 'Server news is on the next page.' --title "Server News" --from Server
/mba sla onlineplayers 'Thanks for playing today!' --title Thanks --from VoteRewards --delay 30
Notes:
- Admin/server/API Book Letters do not include reply links.
allplayersandonlineplayersare supported.- Multiple specific recipients can be comma-separated.
- In network mode,
onlineplayerssupports network-aware online recipient handling.
COD Item-Currency Support
COD packages now support expanded item-currency pricing.
Supported examples:
100
diamond:4,gold_nugget:2,xp:100
100,diamond:3
t:rare_sword:1,xp:250
Supported COD price types:
- Vault money
- Item currency
- XP currency
- Saved item templates
- Combined prices
For admin/API COD mail, r:<returnPlayer> controls both:
- COD payment return
- Declined COD package content return
If no return recipient is provided on admin/API COD mail, returned payments or declined contents use the existing sink behavior.
Package Display Updates
Package display colors were updated for clearer inbox previews and admin management.
| Package Type | Display Item |
|---|---|
| Standard Package | Shulker Box |
| COD Package Pending | Red Shulker Box |
| COD Package Accepted | Blue Shulker Box |
| Returned COD Package | Yellow Shulker Box |
| COD Item-Currency Payment | Purple Shulker Box |
Admin Inbox Check Improvements
The admin inbox check flow has been improved.
Book Letter admin inbox behavior:
- Left-click reads a Book Letter.
- Right-click deletes a Book Letter.
- Admins do not take Book Letters from player inboxes.
- Admin-read player Book Letters hide Reply.
- Admin-read player Book Letters show Back to Player Inbox.
Package admin inbox behavior:
- Package items now clearly show right-click management lore.
- Standard packages, COD packages, returned COD packages, and related package mail types can be managed safely from admin inbox check.
API 5.1.0
MailboxGUI API 5.1.0 is available for developers.
Maven dependency:
<dependency>
<groupId>io.github.rismr1</groupId>
<artifactId>mailboxgui-api</artifactId>
<version>5.1.0</version>
<scope>provided</scope>
</dependency>
API additions include:
- Book Letter mail requests
- Book Letter delivery type
- COD item-currency payment delivery type
- COD price text in delivery events and network payloads
- Book Letter delivery events
- Item-currency COD payment delivery events
New/updated API concepts include:
BookLetterMailRequest
sendBookLetter
MailDeliveryType.BOOK_LETTER
MailDeliveryType.COD_ITEM_CURRENCY_PAYMENT
codPriceText
MailboxGUI-DiscBridge Compatibility
MailboxGUI-DiscBridge 1.1.0 or newer is recommended with MailboxGUI 5.1.0.
DiscBridge 1.1.0 adds support for:
- Book Letter Discord notifications
- COD item-currency payment Discord notifications
{price}placeholder support for MailboxGUI 5.1.0codPriceText- Discord message language files
- Player-selectable Discord DM language
Network Mode Validation
MailboxGUI 5.1.0 has been validated for network-mode safety with MySQL and Redis.
Validated areas include:
- Book Letter send/read/reply behavior
- Book Letter draft cleanup
- COD item-currency parsing
- COD item-currency storage
- COD accept/decline flow
- COD payment return flow
- Admin command delivery
- Delayed mail
- Cross-backend inbox access
- Network locks
- DiscBridge notification payloads
- No mail data corruption during tested flows
Config, Language, and Data Updates
MailboxGUI 5.1.0 includes these internal version updates:
| File/Data Type | Version |
|---|---|
| Config | 12 |
| Language files | 13 |
| Mail data | 5 |
The mail data upgrade refreshes older package mail so package, COD, XP, and item-currency package inbox items use the current preview and admin management lore.
Update Checklist
Before updating:
- Stop the server.
- Back up your server.
- Back up
/plugins/MailboxGUI/. - Replace the old MailboxGUI jar with MailboxGUI 5.1.0.
- If using DiscBridge, update MailboxGUI-DiscBridge to 1.1.0 or newer.
- Start the server.
- Check console for startup warnings.
- Test
/mailbox. - Test sending a Classic Letter.
- Test sending a Book Letter.
- Test opening received mail.
- Test COD package flow if your server uses COD.
- Test network mode if your server uses MySQL/Redis network mail.
Summary
MailboxGUI 5.1.0 adds Book Letters, expands COD item-currency support, updates API delivery payloads, improves admin inbox management, validates network-mode safety, and adds required compatibility for Paper/Purpur 26.2.x.
Information
| Published on | June 23, 2026 |
|---|---|
| Downloads | 14 |