New features in 2.3.0.beta9
Unicode username support
While Discourse has long supported Unicode Full Names for users, usernames had been restricted to ASCII characters only. Site admins can now allow use of Unicode characters is usernames and group names via the unicode usernames site setting. Admins can also limit which unicode characters can be used with the unicode username character whitelist site setting.
Staff Notices
In Discourse 2.3.0.beta4 we added a special call-out notice for new/returning users. Staff can now add custom call-outs above posts, which appear similar to the new user first post call-out.
Review Queue Improvements
First released in Discourse 2.3.0.beta7, the review queue has continued to see improvements and bug fixes. Recent changes include improved clarity for user and post approval actions vs flags, fixes for previously approved users appearing in the queue, fixes for incorrect reviewable scores, an improved review queue layout for small screens and more. On the user side, weâve added a new notification when their pending post is approved, and also show the pending post in the topic view for the post author so it no longer âdisappearsâ.
Digest email unsubscribe improvements
We donât want users to receive emails that they do not want. We make unsubscribing easy, with a link in the footer as well as by replying with the word unsubscribe in the body. Sometimes, however, users just want less emails, not none. Now they are given the option of how frequently they want to receive digest emails, in addition to the option to fully unsubscribe.
Suggested unread topics are now restricted to 90 day old topics
See the linked #feature:announcements topic from Sam for full details:
Multiple SCSS file support for themes
See the linked #howto:devs topic from David for full details:
User preference for title counter mode
Previously, when a Discourse site was in a background tab, the tab title is updated with a counter of new topics/posts within the tab. Now, the count indicated the number of notifications. Users can update choose whichever option they prefer with the new Background page title displays count of user preference (interface tab).
Account Activation Reminder email
Users who do not activate their accounts now receive a single reminder email 2 days after they first sign up.
New groups page layout
Weâve updated the layout the groups page to feel less like an admin page (which it previously was). Groups are now displayed in a card layout, and displays the group full name, group icon, and description. Groups can also be quickly searched for, and filtered by type.
Improved local-dates form
Need to insert a date/time into your post, but have users in different timezones? Take advantage of local-dates, which displays the date/time in the local timezone for the user viewing the post. No need to list the date is 5 timezones, let Discourse do the work for you! Dates/times can be a single point in time, or a range from one time to another. For complicated cases, users can enable advanced mode to modify the date/time display format, enable recurrence, and more.
To insert a local-date, click the calendar icon from the composer toolbar. 
Sample local date: 2019-04-26T20:00:00Z (April 26, 4PM EDT)
Improved category setting organization
Categories have a large number of settings out of the box, and many Discourse plugins add even more. Category settings are now organized into categories to make finding the right setting easier. The settings tab layout has also been standardized so all input fields are the same size.
