Addendum: When this post was first published, the download link was linked to the wrong release candidate for download. Now the link has been update. Sorry for the confusion. (Updated @ 1:26 PM on June 26th).
This release candidate is different from the previous two. So if you’ve been testing RC1 or RC2, you will not be able to upgrade them with this release candidate. You will need to do a new installation for testing. When creating a new database, make sure to use the correct collation: utf8mb4_unicode_ci. This release also includes a few updated plugins and modules for testing with the exception of the communication’s module.
If you find any bugs or issues, please post them in the correct release candidate forum for easier tracking. Also, make sure to check out any new or updated articles that have been tagged 6.3.0, any new code changes that have been tagged 6.3.0 as well as the Youtube channel for a couple of new videos that have been posted.
For more information on other changes you should be aware of, click here to download the information sheet.