Feature/liquid glass

docs/FormEditor/createStylesheet.md

@@ -217,8 +217,8 @@ Available media features and values:
 
 |Media features|Values|Description|
 |---|---|---|
-|`prefers-color-scheme`|<li>**light**</li><li>**dark**</li>|Color scheme to use|
-|`form-theme`|<li>**fluent-ui**</li><li>**win-classic**</li>|Platform theme to use (Windows). For more information on **fluent-ui** theme, refer to [this section](./forms.md#fluent-ui-rendering)|
+|`prefers-color-scheme`|<ul><li>**light**</li><li>**dark**</li></ul>|Color scheme to use|
+|`form-theme`|<ul><li>**fluent-ui**</li><li>**win-classic**</li><li>**liquid-glass**</li><li>**mac-classic**</li></ul>|Platform theme to use. For more information on **fluent-ui** theme, refer to [this section](./forms.md#fluent-ui-rendering).|
 
 
 :::note

docs/Notes/updates.md

@@ -5,20 +5,26 @@ title: Release Notes
 
 ## 4D 21 R3
 
-
 #### Highlights
 
 - The [`JSON Validate`](../commands/json-validate) command now supports of JSON Schema draft 2020-12. 
 - 4D Write Pro now supports [hierarchical list style sheets](../user-legacy/stylesheets.md#hierarchical-list-style-sheets), enabling the creation and management of structured [multi-level lists](../WritePro/user-legacy/using-a-4d-write-pro-area.md#multi-level-lists) with automatic numbering.
 - Ability to use a custom certificate from the macOS keychain instead of a local certificates folder in [`HTTPRequest`](../API/HTTPRequestClass.md#4dhttprequestnew) and [`HTTPAgent`](../API/HTTPAgentClass.md#4dhttpagentnew) classes. 
 - New [`4D.Method` class](../API/MethodClass.md) to create and execute a 4D method code from text source. [`METHOD Get path`](../commands/method-get-path) and [`METHOD RESOLVE PATH`](../commands/method-resolve-path) commands support a new `path volatile method` constant (128).
 
+
+#### Support of Liquid glass on macOS
+
+- Automatic support of [**Liquid glass** interface](https://www.apple.com/newsroom/2025/06/apple-introduces-a-delightful-and-elegant-new-software-design/) with 4D on macOS 26 Tahoe. See [this blog post](https://blog.4d.com/the-new-macos-tahoe-design-comes-to-your-4d-applications) for detailed information. 
+- New values returned by the [`FORM Theme`](../commands/form-theme) command and [CSS Media queries](../FormEditor/createStylesheet.md#media-queries). 
+- To help developers gradually adapt their interfaces, ability to **disable Liquid glass in 4D engine-based applications** via the "UIDesignRequiresCompatibility" key in the application's *Info.plist* file (see [Apple's documentation about this key](https://developer.apple.com/documentation/BundleResources/Information-Property-List/UIDesignRequiresCompatibility)).
+
+
 #### Behavior changes
 
 - The [`JSON Validate`](../commands/json-validate) command now takes the *$schema* key into account and generates an error if a non-supported version is declared in the schema. 
 - For clarity, formula objects are now instances of a new [`4D.Formula`](../API/FormulaClass.md) class that inherits from the generic [`4D.Function`](../API/FunctionClass.md) class.
 
-
 ## 4D 21 R2
 
 Read [**What’s new in 4D 21 R2**](https://blog.4d.com/whats-new-in-4d-21-r2/), the blog post that lists all new features and enhancements in 4D 21 R2.

docs/language-legacy/Forms/form-theme.md

@@ -11,7 +11,7 @@ displayed_sidebar: docs
 
 | Parameter | Type |  | Description |
 | --- | --- | --- | --- |
-| Function result | Text | ← | Theme used by the current form: "Classic" or "FluentUI" (Windows) |
+| Function result | Text | &#8592; | Theme used by the current form:<ul><li>Windows: "Classic" or "FluentUI"</li><li>macOS: "Classic" or "LiquidGlass"</li></ul>|
 </div>
 <!-- END REF-->
 
@@ -20,23 +20,33 @@ displayed_sidebar: docs
 
 |Release|Changes|
 |---|---|
+|21 R3|Support of LiquidGlass on macOS |
 |21 R2|Added|
 
 </details>
 
 
 ## Description 
 
-<!--REF #_command_.FORM theme.Summary-->The **FORM theme** command returns the Windows theme actually rendered for the current form: "Classic" or "FluentUI".<!-- END REF-->
+<!--REF #_command_.FORM theme.Summary-->The **FORM theme** command returns the OS interface theme rendered for the current form: "FluentUI" (Windows), "LiquidGlass" (macOS), or "Classic" (all platforms).<!-- END REF-->
+
+If there is no current form, **FORM theme** returns an empty string. 
+
+### Windows
 
 The Windows form rendering theme can be defined at [application level](../../settings/interface.md#use-fluent-ui-on-windows) and/or at [form level](../../FormEditor/properties_FormProperties.md#form-theme-on-windows) (where it can be inherited or explicitely defined), and also depends on the [availability of specific Microsoft libraries](../../FormEditor/forms.md#requirements) on the current machine at runtime. This command allows you to know which form theme is currently running. 
 
-If there is no current form, or if the command is executed on macOS, **FORM theme** returns an empty string. 
+### macOS
+
+As of version 21 R3, 4D and 4D Server run natively under Liquid Glass interface on macOS 26 Tahoe. This rendering is automatically used and cannot be disabled, [except in engine-based applications](https://blog.4d.com/the-new-macos-tahoe-design-comes-to-your-4d-applications) as a transitional measure to give developers additional time to adapt their forms. 
+
 
 
 ## See also 
 
 [Fluent UI rendering](../../FormEditor/forms.md#fluent-ui-rendering)  
+[(blog post) Deploy Fluent UI effortlessly in your 4D applications](https://blog.4d.com/deploy-fluent-ui-effortlessly-in-your-4d-applications/)   
+[(blog post) The new macOS Tahoe design comes to your 4D applications](https://blog.4d.com/the-new-macos-tahoe-design-comes-to-your-4d-applications)
 
 ## Properties