diff --git a/docs/FormEditor/createStylesheet.md b/docs/FormEditor/createStylesheet.md
index 8e89d021d01dfe..4a88cbe63bdaf2 100644
--- a/docs/FormEditor/createStylesheet.md
+++ b/docs/FormEditor/createStylesheet.md
@@ -217,8 +217,8 @@ Available media features and values:
|Media features|Values|Description|
|---|---|---|
-|`prefers-color-scheme`|
**light****dark**|Color scheme to use|
-|`form-theme`|**fluent-ui****win-classic**|Platform theme to use (Windows). For more information on **fluent-ui** theme, refer to [this section](./forms.md#fluent-ui-rendering)|
+|`prefers-color-scheme`||Color scheme to use|
+|`form-theme`|- **fluent-ui**
- **win-classic**
- **liquid-glass**
- **mac-classic**
|Platform theme to use. For more information on **fluent-ui** theme, refer to [this section](./forms.md#fluent-ui-rendering).|
:::note
diff --git a/docs/Notes/updates.md b/docs/Notes/updates.md
index d4ad58069d3426..f8ba705414a3c3 100644
--- a/docs/Notes/updates.md
+++ b/docs/Notes/updates.md
@@ -5,7 +5,6 @@ title: Release Notes
## 4D 21 R3
-
#### Highlights
- The [`JSON Validate`](../commands/json-validate) command now supports of JSON Schema draft 2020-12.
@@ -13,12 +12,19 @@ title: Release Notes
- 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.
diff --git a/docs/language-legacy/Forms/form-theme.md b/docs/language-legacy/Forms/form-theme.md
index 830bca2f183690..5552c10ba04512 100644
--- a/docs/language-legacy/Forms/form-theme.md
+++ b/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 | ← | Theme used by the current form:- Windows: "Classic" or "FluentUI"
- macOS: "Classic" or "LiquidGlass"
|
@@ -20,6 +20,7 @@ displayed_sidebar: docs
|Release|Changes|
|---|---|
+|21 R3|Support of LiquidGlass on macOS |
|21 R2|Added|
@@ -27,16 +28,25 @@ displayed_sidebar: docs
## Description
-The **FORM theme** command returns the Windows theme actually rendered for the current form: "Classic" or "FluentUI".
+The **FORM theme** command returns the OS interface theme rendered for the current form: "FluentUI" (Windows), "LiquidGlass" (macOS), or "Classic" (all platforms).
+
+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