⏳ Background won't save, an error appears instead

### Description

I did a fresh install on my website, activated V4 to test, instantly ran into issues with background elements. Tried on atomic tabs, tried on an atomic heading widget, anytime I add a background element I get an invalid styles error message.


### Steps to reproduce

Started a new page, inserted the atomic element, changed the background styling, tried to save the page.

### Expected behavior

Should save the page without a warning.

### Elementor System Info

Click to reveal

```txt
== Server Environment ==
Operating System: Linux
Software: Apache
MySQL version: Source distribution v8.4.6-6
PHP Version: 8.2.30
PHP Memory Limit: 768M
PHP Max Input Vars: 3000
PHP Max Post Size: 256M
GD Installed: Yes
ZIP Installed: Yes
Write Permissions: All right
Elementor Library: Connected

== WordPress Environment ==
Version: 6.9.4
Site URL: https://v4.chattercreative.co
Home URL: https://v4.chattercreative.co
WP Multisite: No
Max Upload Size: 256 MB
Memory limit: 256M
Max Memory limit: 768M
Permalink Structure: /%category%/%postname%/
Language: en_US
Timezone: America/New_York
Debug Mode: Inactive

== Theme ==
Name: Hello Elementor
Version: 3.4.7
Author: Elementor Team
Child Theme: No

== User ==
Role: administrator
WP Profile lang: en-US
User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/146.0.0.0 Safari/537.36

== Active Plugins ==
Classic Editor
Version: 1.6.7
Author: WordPress Contributors

Duplicate Page
Version: 4.5.6
Author: mndpsingh287

Elementor
Version: 4.0.1
Author: Elementor.com

Elementor Pro
Version: 4.0.1
Author: Elementor.com

JetEngine
Version: 3.8.8
Author: Crocoblock

Perfect Images: Regenerate Thumbnails, Image Sizes, WebP & AVIF
Version: 7.1.4
Author: Jordy Meow

Security Optimizer
Version: 1.6.0
Author: SiteGround

SEOPress
Version: 9.7.4
Author: The SEO Guys at SEOPress

SEOPress PRO
Version: 9.4.1
Author: The SEO Guys at SEOPress

Site Kit by Google
Version: 1.176.0
Author: Google

Speed Optimizer
Version: 7.7.8
Author: SiteGround

WP Ultimate CSV Importer Pro
Version: 8.0
Author: Smackcoders

== Features ==
Custom Fonts: 0
Custom Icons: 0

== Integrations ==

== Elementor Experiments ==
Inline Font Icons: Inactive by default
Additional Custom Breakpoints: Active by default
Container: Active
Optimized Markup: Inactive by default
Default to New Theme Builder: Active by default
Header & Footer: Active by default
Pro Free Trial Popup: Inactive by default
Nested Elements: Active
Pages Panel: Inactive by default
Atomic Widgets: Active
V4 Indications Popover: Inactive by default
Enforce atomic widgets capabilities: Active by default
Editor MCP for atomic widgets: Active by default
Backward compatibility migrations: Active by default
Global Classes: Active
Enforce global classes capabilities: Active by default
Variables: Active
Variables Manager: Active by default
Editor v4 (Opt In Page): Active by default
Editor V4: Active
Components: Active
Interactions: Active by default
Widget Creation: Active by default
Import/Export Customization: Active by default
Elementor Editor Events: Inactive by default
Atomic Form: Active by default
Menu: Inactive by default
Size Variables: Active by default
Pro Interactions: Active by default
In-Editor Feedback: Inactive by default

== Log ==

Log: showing 20 of 422025-12-23 16:09:30 [info] Elementor data updater process has been completed. [array (
'plugin' => 'Elementor',
'from' => '3.33.2',
'to' => '3.33.6',
)]
2025-12-23 16:09:32 [info] elementor-pro::elementor_pro_updater Started
2025-12-23 16:09:32 [info] Elementor Pro/Upgrades - _on_each_version Start
2025-12-23 16:09:32 [info] Elementor Pro/Upgrades - _on_each_version Finished
2025-12-23 16:09:32 [info] Elementor data updater process has been completed. [array (
'plugin' => 'Elementor Pro',
'from' => '3.33.1',
'to' => '3.34.0',
)]
2026-01-07 11:09:11 [info] Elementor data updater process has been queued. [array (
'plugin' => 'Elementor',
'from' => '3.33.6',
'to' => '3.34.1',
)]
2026-01-07 11:09:21 [info] elementor::elementor_updater Started
2026-01-07 11:09:21 [info] Elementor/Upgrades - _on_each_version Start
2026-01-07 11:09:21 [info] Elementor/Upgrades - _on_each_version Finished
2026-01-07 11:09:21 [info] Elementor data updater process has been completed. [array (
'plugin' => 'Elementor',
'from' => '3.33.6',
'to' => '3.34.1',
)]
2026-04-13 09:49:44 [info] Elementor data updater process has been queued. [array (
'plugin' => 'Elementor',
'from' => '3.34.1',
'to' => '4.0.1',
)]
2026-04-13 09:49:45 [info] elementor::elementor_updater Started
2026-04-13 09:49:45 [info] Elementor/Upgrades - _on_each_version Start
2026-04-13 09:49:45 [info] Elementor/Upgrades - _on_each_version Finished
2026-04-13 09:49:45 [info] Elementor data updater process has been completed. [array (
'plugin' => 'Elementor',
'from' => '3.34.1',
'to' => '4.0.1',
)]
2026-04-13 09:51:33 [info] Elementor data updater process has been queued. [array (
'plugin' => 'Elementor Pro',
'from' => '3.34.0',
'to' => '4.0.1',
)]
2026-04-13 09:51:37 [info] elementor-pro::elementor_pro_updater Started
2026-04-13 09:51:37 [info] Elementor Pro/Upgrades - _on_each_version Start
2026-04-13 09:51:37 [info] Elementor Pro/Upgrades - _on_each_version Finished
2026-04-13 09:51:37 [info] Elementor data updater process has been completed. [array (
'plugin' => 'Elementor Pro',
'from' => '3.34.0',
'to' => '4.0.1',
)]

PHP: showing 1 of 1PHP: 2026-04-13 10:06:31 [warning X 1][/home/customer/www/v4.chattercreative.co/public_html/wp-content/plugins/elementor/modules/history/revisions-manager.php::363] Undefined array key "editor_post_id" [array (
'trace' => '
#0: Elementor\Core\Logger\Manager -> shutdown()
',
)]

== Elementor - Compatibility Tag ==

Elementor Pro: Compatible

== Elementor Pro - Compatibility Tag ==

```

### Agreement

- [x] I confirm I have read and followed all the guidelines and instructions outlined in the Editor V4 Bug Report form.
- [x] I agree that my issue may be closed without further action if it doesn't meet all the requirements outlined in the Editor V4 Bug Report form.