[wp-trac] [WordPress Trac] #63589: Unable to live preview changes to Additional CSS in the Customizer when using a Block Theme

[WordPress Trac]

#63589: Unable to live preview changes to Additional CSS in the Customizer when
using a Block Theme
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 Reporter:  westonruter              |       Owner:  westonruter
     Type:  defect (bug)             |      Status:  accepted
 Priority:  normal                   |   Milestone:  6.9
Component:  Customize                |     Version:  6.2
 Severity:  normal                   |  Resolution:
 Keywords:  has-patch needs-testing  |     Focuses:
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Comment (by poojapadamad):

 == Test Report
 === Description
 This report validates whether the indicated patch works as expected.

 Patch tested: https://github.com/WordPress/wordpress-develop/pull/9000

 === Environment
 - WordPress: 6.9-alpha-20250708.025501
 - PHP: 7.4.31-dev
 - Server: PHP.wasm
 - Database: WP_SQLite_Driver (Server: 5.5 / Client: 3.40.1)
 - Browser: Chrome 138.0.0.0
 - OS: macOS
 - Theme: Twenty Twenty-Five 1.2
 - MU Plugins: None activated
 - Plugins:
   * Test Reports 1.2.0

 === Actual Results
 1. ✅Changes reflect immediately in the preview pane when colour is
 changed directly from Customizer
 2. ❌Changes do not reflect in the preview pane on changing colour from
 Additional CSS in Styles.

 === Testing Steps:

 From Customizer:
 Activate the Twenty Twenty-Five theme.
 Navigate directly to the Customizer:/wp-admin/customize.php
 Go to the Additional CSS section.
 Add a CSS:p { color: red; }
 Observe the preview panel.

 From Styles:
 Activate the Twenty Twenty-Five theme.
 Go to Appearance > Editor >Styles >Blocks > Code
 Go to the Additional CSS section.
 Add a CSS:p { color: red; }
 Observe the preview panel.

 === Supplemental Artifacts

-- 
Ticket URL: <https://core.trac.wordpress.org/ticket/63589#comment:18>
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