added FF release notes for line-clamp property (#45008)

* added FF release notes for line-clamp property

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

Co-authored-by: Dipika Bhattacharya <dipika@foss-community.org>

* Update files/en-us/mozilla/firefox/releases/154/index.md

Co-authored-by: Dipika Bhattacharya <dipika@foss-community.org>

---------

Co-authored-by: Dipika Bhattacharya <dipika@foss-community.org>

Author: dletorey

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

@@ -435,6 +435,20 @@ The {{cssxref("link-parameters")}} CSS property and {{cssxref("param")}} CSS fun
 - `layout.css.link-parameters.enabled`
   - : Set to `true` to enable.
 
+### Truncating content with `line-clamp`
+
+The {{cssxref("line-clamp")}} CSS property now works without the `-webkit-` vendor prefix, though at this stage it does not support the `no-ellipsis` and `<string>` values. ([Firefox bug 2042986](https://bugzil.la/2042986)).
+
+| Release channel   | Version added | Enabled by default? |
+| ----------------- | ------------- | ------------------- |
+| Nightly           | 154           | No                  |
+| Developer Edition | 154           | No                  |
+| Beta              | 154           | No                  |
+| Release           | 154           | No                  |
+
+- `layout.css.line-clamp.enabled`
+  - : Set to `true` to enable.
+
 ## SVG
 
 **No experimental features in this release cycle.**

files/en-us/mozilla/firefox/releases/154/index.md

@@ -86,3 +86,7 @@ Firefox 154 is the current [Beta version of Firefox](https://www.firefox.com/en-
 These features are shipping in Firefox 154 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.
+
+- **Truncating content with `line-clamp`**: `layout.css.line-clamp.enabled`
+
+  The {{cssxref("line-clamp")}} CSS property now works without the `-webkit-` vendor prefix, though at this stage it does not support the `no-ellipsis` and `<string>` values. ([Firefox bug 2042986](https://bugzil.la/2042986)).