This extension automatically redirect to the slack link with your browser, not open slack app. Nothing more, nothing less. You don't have to download and install slack app in your machine once you install this extension. You can continue to use slack through a Chrome browser. If you are feeling irritated with "Opening link in Slack... You will be redirected in a few moments. Don't have the app yet? Download Slack for Desktop Or, you can open this link in your browser" No more getting annoyed. You don't need to install Slack App. スラックのリンクをブラウザで開くとappを開こうとしてきます。 このextensionはappを開くことなくブラウザのままリンクに飛ぶようにするだけのシンプルな拡張機能です。