Add snug mode release notes

CHANGELOG.txt

@@ -39,6 +39,7 @@ Changelog
  * Update `DOCUMENT_PASSWORD_REQUIRED_TEMPLATE` setting to `WAGTAILDOCS_PASSWORD_REQUIRED_TEMPLATE` with deprecation of previous naming (Saksham Misra, LB (Ben) Johnston)
  * When editing settings (contrib) use the same icon in the editing view that was declared when registering the setting (Vince Salvino, Rohit Sharma)
  * Populate django-treebeard cache during page routing to improve performance of `get_parent` (Nigel van Keulen)
+ * Add a new user profile preference to configure user interface information density (Thibaud Colas)
  * Fix: Fix typo in `__str__` for MySQL search index (Jake Howard)
  * Fix: Ensure that unit tests correctly check for migrations in all core Wagtail apps (Matt Westcott)
  * Fix: Correctly handle `date` objects on `human_readable_date` template tag (Jhonatan Lopes)

docs/advanced_topics/customisation/admin_templates.md

@@ -124,7 +124,9 @@ For static colors, either set each color separately (for example `--w-color-prim
 
 ```
 
-## Custom user interface information density
+(custom_ui_information_density)=
+
+## Custom UI information density
 
 To customize information density of the admin user interface, inject a CSS file using the hook [](insert_global_admin_css). Set the `--w-density-factor` CSS variable to increase or reduce the UI density. The default value is `1`, the "snug" UI theming uses `0.5`. Here are example overrides:
 

docs/releases/6.1.md

@@ -11,7 +11,7 @@ depth: 1
 
 ## What's new
 
-## Universal listings continued
+### Universal listings continued
 
 Continuing work on the Universal Listings project, this release rolls out universal listing styles for the following views:
 
@@ -27,6 +27,15 @@ Continuing work on the Universal Listings project, this release rolls out univer
 
 Universal listing components like header buttons have also been tweaked to improve usability. This feature was developed by Ben Enright and Sage Abdullah.
 
+### Information-dense admin interface
+
+Wagtail now provides a way for CMS users to control the information density of the admin interface, via their user profile preferences.
+The new setting allows switching between the "default" density and a new "snug" mode, which reduces the spacing and size of UI elements.
+
+It’s also possible for site implementers to customize this for the needs of their project – see [](custom_ui_information_density).
+
+This feature was developed by Ben Enright and Thibaud Colas.
+
 ### Other features
 
  * Refine wording of page & collection privacy using password is a shared password and should not be used for secure content (Rohit Sharma, Jake Howard)