Most important change in this release is the improved forum.
The structure of the library directory has been changed. All Banshee-related libraries have been moved to /libraries/banshee/ so that third party libraries or your own can be placed in /libraries/. More easier for you to reach your own libraries.
The way layouts are included have been changes. With this new method, you can always use /content/layout/ in your XSLT to reach layout parameters set via $this->view.
This release allows you to add dynamic content to static pages. The password hash algorithm has been upgraded to Argon2, which makes Banshee require PHP v7.2.
The most interesting new feature in this version is the preview option of a forum comment before submitting it. Other new things are the improved BBcode check and the spam check for page forms.