⏳ Error when importing JSON directly in Editor (4.0.x) – works in backend and with 3.35.9

### Description

When trying to import a .json template directly in the Elementor Editor (via the folder icon), I receive the following error:
Error occurred, this source does not support import
Important details:

Importing the same JSON file via Elementor → Templates → Import Templates (backend) works without any problem.
When trying to import a .json template directly in the Elementor Editor (via the folder icon), the following error appears:
Error occurred, this source does not support import

Key points:

Importing the same JSON file via Elementor → Templates → Import Templates (in the dashboard) works perfectly.
The problem only occurs with the direct import inside the Editor.
Updating to Elementor Core 4.0.1 introduced the issue.
Rolling back to Elementor Core 3.35.9 (keeping Elementor Pro 4.0.1) completely resolves the problem.

Environment:

WordPress 6.9.4 (Multisite)
Elementor Core: 4.0.1 (broken) → 3.35.9 (working)
Elementor Pro: 4.0.1
Theme: Hello Elementor
PHP: 8.4.19

Additional notes:
The issue appears on multiple sites in the network. Clearing cache, Safe Mode, and deactivating all other plugins did not help.

### Steps to reproduce

1. Use Elementor Core 4.0.1 + Pro 4.0.1
2. Open any page with the Elementor Editor
3. Click the folder icon → Import Template → select a .json file
4. After confirming the unsafe JSON warning, the error occurs.

### Expected behavior

The template should import successfully directly in the editor.

### Elementor System Info

Click to reveal

```txt
== Server Environment ==
Operating System: Linux
Software: Apache
MySQL version: Debian 12 v10.11.6-MariaDB-0+deb12u1
PHP Version: 8.4.19
PHP Memory Limit: 1024M
PHP Max Input Vars: 1000
PHP Max Post Size: 16M
GD Installed: Yes
ZIP Installed: Yes
Write Permissions: All right
Elementor Library: Connected

== WordPress Environment ==
Version: 6.9.4
Site URL: https://kk-talents.com/in
Home URL: https://kk-talents.com/in
WP Multisite: Yes
Max Upload Size: 16 MB
Memory limit: 1024M
Max Memory limit: 1024M
Permalink Structure: /%postname%/
Language: en_US
Timezone: Europe/Berlin
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 ==
FluentCRM - Marketing Automation For WordPress
Version: 2.9.87
Author: WP Email Newsletter Team - FluentCRM

FluentCRM Pro
Version: 2.9.86
Author: Fluent CRM

== Network Plugins ==
Advanced Custom Fields
Version: 6.8.0
Author: WP Engine

Advanced Custom Fields Multilingual
Version: 2.2.2
Author: OnTheGoSystems

Code Snippets
Version: 3.9.5
Author: Code Snippets Pro

Duplicator Pro
Version: 4.5.25.2
Author: Duplicator

Elementor
Version: 3.35.9
Author: Elementor.com

Elementor Pro
Version: 4.0.1
Author: Elementor.com

FluentSMTP
Version: 2.2.95
Author: FluentSMTP & WPManageNinja Team

Hreflang Manager
Version: 1.50
Author: DAEXT

MalCare WordPress Security Plugin - Malware Scanner, Cleaner, Security Firewall
Version: 6.39
Author: MalCare Security

NS Cloner - Site Copier
Version: 4.4.9.1
Author: Never Settle

PhastPress
Version: 3.9
Author: Albert Peschar

Slim SEO
Version: 4.9.4
Author: Slim SEO

Wordfence Security
Version: 8.1.4
Author: Wordfence

WP-Sweep
Version: 1.1.8
Author: Lester 'GaMerZ' Chan

WP Fastest Cache
Version: 1.4.6
Author: Emre Vona

WP Meteor
Version: 3.4.17
Author: Aleksandr Guidrevitch

WPML Media Translation
Version: 3.1.0
Author: OnTheGoSystems

WPML Multilingual CMS
Version: 4.9.2
Author: OnTheGoSystems

WPML String Translation
Version: 3.5.1
Author: OnTheGoSystems

== Must-Use Plugins ==
Force Hello Elementor Network-wide
Version: 1.0
Author:

== Features ==
Custom Fonts: 1
Custom Icons: 0

== Integrations ==

== Elementor Experiments ==
Inline Font Icons: Active
Additional Custom Breakpoints: Inactive
Container: Active
Optimized Markup: Active
Default to New Theme Builder: Inactive
Header & Footer: Inactive
Pro Free Trial Popup: Active by default
Nested Elements: Active
Pages Panel: Inactive by default
Elementor Home Screen: Active by default
Atomic Widgets: Inactive by default
Global Classes: Inactive by default
Enforce global classes capabilities: Active by default
Variables: Active by default
Cloud Library: Active
Editor v4 (Opt In Page): Active by default
Editor V4: Inactive by default
Components: Active by default
Interactions: Active by default
Editor one: Active by default
Import/Export Customization: Active by default
Elementor Editor Events: Active by default
Atomic Form: Active by default
Menu: Inactive
Size Variables: Active by default
Pro Interactions: Active by default
In-Editor Feedback: Inactive by default

== Log ==

== Elementor - Compatibility Tag ==

== Elementor Pro - Compatibility Tag ==

```

### Agreement

- [ ] I confirm I have read and followed all the guidelines and instructions outlined in the Elementor 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 Elementor Bug Report form.