added experimental release note for text-autospace (#40966)

* added experimental release note for text-autospace

* Update files/en-us/mozilla/firefox/experimental_features/index.md

Co-authored-by: Vadim Makeev <hi@pepelsbey.dev>

---------

Co-authored-by: Vadim Makeev <hi@pepelsbey.dev>

Author: dletorey

files/en-us/mozilla/firefox/experimental_features/index.md

@@ -350,6 +350,20 @@ The {{CSSXRef(":heading")}} pseudo-class allows you to style all [heading elemen
 - `layout.css.heading-selector.enabled`
   - : Set to `true` to enable.
 
+### `text-autospace` property
+
+The **`text-autospace`** CSS property allows you to specify the space applied between Chinese/Japanese/Korean (CJK) and non-CJK characters. Currently these values are only parsed and there is no effect on the output. ([Firefox bug 1869577](https://bugzil.la/1869577)).
+
+| Release channel   | Version added | Enabled by default? |
+| ----------------- | ------------- | ------------------- |
+| Nightly           | 143           | No                  |
+| Developer Edition | 143           | No                  |
+| Beta              | 143           | No                  |
+| Release           | 143           | No                  |
+
+- `layout.css.text-autospace.enabled`
+  - : Set to `true` to enable.
+
 ## SVG
 
 **No experimental features in this release cycle.**

files/en-us/mozilla/firefox/releases/143/index.md

@@ -83,6 +83,10 @@ Firefox 143 is the current [Beta version of Firefox](https://www.firefox.com/en-
 
 ## Experimental web features
 
+- **`text-autospace`**: `layout.css.text-autospace.enabled`
+
+  The **`text-autospace`** CSS property allows you to specify the space applied between Chinese/Japanese/Korean (CJK) and non-CJK characters. Currently these values are only parsed and there is no effect on the output. ([Firefox bug 1869577](https://bugzil.la/1869577)).
+
 These features are shipping in Firefox 143 but are disabled by default.
 To experiment with them, search for the appropriate preference on the `about:config` page and set it to `true`.
 You can find more such features on the [Experimental features](/en-US/docs/Mozilla/Firefox/Experimental_features) page.