You can access Messenger with the quick links on the extension's popup: new messages, unread, requests and archived messages.
You can rearrange the buttons in the order you like. Just press the image, drag it to the new location and drop it.
The extension do not collect your Facebook information. The notifications about new messages are stored only on your browser.
Update log:
Initially released as an Chrome App in 2016, Notifications for Messenger was made available as Chrome extension in January 2018.
Disclaimer: This Chrome extension have no affiliations with the popular social network website Facebook. All copyrights belong to their respective owners. Facebook doesn’t endorse or sponsor this Chrome extension. It is not owned by, is not licensed by and is not a subsidiary of Facebook Inc. Facebook is trademark of Facebook Inc.
Thank you for using this Chrome extension.