adding my features to release notes

Author: sandy081

release-notes/images/1_100/extensions-agent-tool.mp4

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:4dde70ed34f7965a31d08a68513644caa0b7d708e435d4f6e2b00ae2b32d45b4
+size 194911

release-notes/v1_100.md

@@ -110,6 +110,12 @@ Configure what is attached to chat with:
 
 This experimental feature is enabled by default for all Simple Browsers, but can be disabled with `setting(chat.sendElementsToChat.enabled)`.
 
+### Extensions tool
+
+Use `#extensions` tool to find extensions from the Marketplace. This tool is available in both chat and agent mode and is picked up automatically but you can also reference it explicitly via `#extensions` with your query. The tool will return a list of extensions that match your query, and you can install them directly from the results.
+
+<video src="images/1_100/extensions-agent-tool.mp4" title="Video that shows using the extensions tool to display popular Java extensions." autoplay loop controls muted></video>
+
 ## Accessibility
 
 ### Merge editor improvements
@@ -166,6 +172,18 @@ By default, the Secondary Side Bar is hidden when you open a new workspace or wi
 
 Note that after a workspace or window has been opened, the visibility becomes a workspace state and overrides the setting value. If you close the Secondary Side Bar, it will remain closed in that workspace or window.
 
+### Mandatory extension signature verification
+
+Extension signature verification is now required on all platforms - Windows, MacOS, and Linux. Previously, this verification was only mandatory on Windows and MacOS. With this release, Linux now also enforces extension signature verification, ensuring that all extensions are properly validated before installation. This change further strengthens security by preventing the installation of potentially malicious extensions. For more details, see the [Extension Signing](https://code.visualstudio.com/docs/configure/extensions/extension-marketplace#_the-extension-signature-cannot-be-verified-by-vs-code).
+
+### Learn more links for malicious extensions
+
+When an extension is identified as malicious, VS Code now provides links to additional information explaining why the extension was flagged. These "Learn More" links connect users to GitHub issues or documentation with details about the security concerns, helping users better understand the potential risks.
+
+### Prevent installation of Copilot chat pre-release versions in VS Code stable
+
+VS Code now prevents the installation of Copilot chat pre-release version in VS Code stable. This helps avoid situations where users inadvertently install the Copilot chat pre-release version and gets stuck in a broken state. This means you can only install the Copilot chat pre-release version in the Insiders build of VS Code.
+
 ## Code Editing
 
 ### NES Import Suggestions
@@ -457,6 +475,5 @@ Contributions to `monaco-editor`:
 
 * [@RoccoC (Rocco Cataldo)](https://github.com/RoccoC): Update webpack plugin to support module workers [PR #4742](https://github.com/microsoft/monaco-editor/pull/4742)
 
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