Native Client (NaCl) was supported through Edge version 115. In 116 to 119, NaCl was only usable by enabling an enterprise policy. Starting with 120 (December 2023), support for NaCl was completely removed.
To enhance web security and performance, Native Client (NaCl) is no longer supported by Microsoft Edge (along with other browsers). WebAssembly (Wasm) is recommended instead of NaCl; see Run compiled code in an extension.
Sidebar extensions
Use the Sidebar API to make your new or existing Microsoft Edge extension appear in the sidebar. Any extension can use the sidebar, in addition to its other UI.
Sidebar extensions are not yet in a stable release of Microsoft Edge.
Users of your extension will be able to report issues through the extension's webpage on the Microsoft Edge Add-ons website. Developer support information will be shown on the product page of an extension. This information will allow users to directly reach out to the extension developer for extension-specific support.
Manifest V2 Microsoft Edge Add-ons deprecation
When this change is released, Microsoft Partner Center will not accept updates to existing Manifest V2 Microsoft Edge Add-ons. Microsoft Edge will no longer support or run Manifest V2 Microsoft Edge Add-ons.
Note that by using Microsoft Edge Enterprise Policies, Enterprise Accounts can allow Manifest V2 Microsoft Edge Add-ons to run and operate on Microsoft Edge.
Manifest V2 Microsoft Edge Enterprise Add-ons cease to function
When this change is released, Microsoft Edge Enterprise Add-ons with Manifest V2 will not be functional on Microsoft Edge.
Plan and execute an endpoint deployment strategy, using essential elements of modern management, co-management approaches, and Microsoft Intune integration.