Hi ff7cbaf6d4e6

Are you talking about 6.13.5? if yes, then it doesn't support utf8mb4 and won't do it in future.
However, meaningful error messages will be provided soon on 6.13.x by way of backporting fixes.

Also, please see the following item for utf8mb4 support: https://jira.atlassian.com/browse/CONFSERVER-53642

Thanks,
Ganesh

Hi philippe.perez, we got the same error with 6.18.5, can I update mysql setting to UTF8MB4?

In doc, it says only confluence with 7.2 or later version can upgrade. Confuse...

Hi philippe.perez, We are looking into backporting the meaningful error messages to 6.13. We will update this ticket once that is completed. Unfortunately, if you are interested in full emoji support in MySQL you will need to upgrade to 7.3 or our upcoming Enterprise Release 7.4. 

Hello,

When will the step 2 be provided in the current LTS version ? That is the 6.13, which is still supported by the Enterprise license so candidate for such backport.

Thanks.

Hi All,

I wanted to follow up on our update above. The Confluence server development team has now completed both item 1 (Support for emoji in MySQL) and item 2 (providing meaningful error messages). We strongly encourage customers to follow the steps outlined in our documentation to migrate from UTF8 to UTF8MB4, completely resolving this issue.

If you are unable to migrate to UTF8MB4 we have added a number of meaningful error messages to Confluence to stop users attempting to add unsupported 4-byte characters. We have added these errors to:

• page publish/save events for pages and blogs 
• page titles
• comment/inline comment saves.

Please note that we have not added this error message to content fields that are less used/less likely to contain 4byte characters including:

• comments accessed via email,
• the editor in Questions for Confluence,
• comments on attachments,
• gadget comments,
• attachment titles
• content added via Confluence Mobile. 

From the Confluence development team, we want to say thank you for everyone who provided feedback as part of both of the fixes mentioned above. We hope you now enjoy an emoji-filled Confluence. 

Regards,

The Confluence Server Team

Atlassian Update - Feb 2020
We have been working on a fix for this issue and wanted to give you an update on where we are up to. Our work in broken down into two key milestones:

1) Support for emoji in MySQL: We have delivered support for UTF8MB4 in Confluence 7.3.1. This work was being tracked in CONFSERVER-53642 - Support MySQL Databases using utf8mb4 and is now Done. Confluence now supports 4 byte unicode characters with MySQL UTF8MB4 collation. To assist customers with existing MySQL databases (that do not support UTF8MB4) we have provided a detailed guide outlining instructions on how to move to a UTF8MB4 compatible MySQL database here.

2) Provide meaningful error messages when adding emoji on instances still with MySQL utf8: To stop users attempting to add unsupported Emoji to Confluence with MySQL utf8, we have added verification to publish/save events for all pages and blogs. This will provide users with a useful message instructing them to remove the character in order to save their content. We expect the message to look something like this:

We have released this change as part of 7.3.1 and will backport this change to the next bugfix release of 6.13 as well. Note we also plan to add this error message to emoji’s included in page titles, comments, inline comments and attachment comments. These will be added in future bugfix releases as they become available. You can continue to track this work in this Jira ticket.

Cheers,
The Confluence Server Team

Works for me as well.  Here's how to update your database.  Stop confluence then update my.cnf:

[client]
default-character-set = utf8mb4
[mysqld]
character-set-server = utf8mb4

Reload or restart mysqld.  Next update all of your tables (there are many):

mysql> SET FOREIGN_KEY_CHECKS = 0;
mysql> ALTER TABLE <all of your tables> convert TO CHARACTER SET utf8mb4 COLLATE utf8mb4_bin;
mysql> SET FOREIGN_KEY_CHECKS = 1;

Start confluence.  Process is similar for Jira - change your database driver from mysql to mysql57 first.  Enjoy 💩

I upgraded to Confluence 7.3.1 and had already used MySQL 5.7.29. 

Good to know.

That means that you also upgraded to Confluence 7.3.1 and your database was in 5.9 ?

Did an update yesterday and it worked fine. Don't forget to update database, tables and columns.

https://confluence.atlassian.com/confkb/how-to-fix-the-collation-and-character-set-of-a-mysql-database-670958160.html