If you ever work in a public space or around snooping people you may want some extra privacy on Slack. Here is a pretty simple solution to enable a blurred overlay when you mouse out of the application.

To add this functionality…
- Enable Slack Developer Tools – You will only need to do this once
- Open a Command Prompt and run
1setx SLACK_DEVELOPER_MENU true
- I am told on a Mac it would be
1export SLACK_DEVELOPER_MENU=true
- Open a Command Prompt and run
- Restart Slack
- Open Developer Tools
- From the application menu select View > Developer > Toggle Webapp DevTools
- Shortcut: Ctrl+Alt+I
- Paste the following script into the Console tab – You will need to do this each time Slack restarts (unless I find a better way to implement this)
12345678(function(){let overlay = document.createElement('div');overlay.setAttribute('id','privacy-overlay');overlay.style.cssText = 'position:absolute; height: 100%;width: 100%; z-index:999; display: none; background: rgba(255,255,255,0.2); backdrop-filter: blur(5px);';overlay.onmouseover = el => el.currentTarget.style.display = 'none';document.body.onmouseleave = el => document.getElementById('privacy-overlay').style.display = 'block';document.body.insertBefore(overlay, document.body.firstElementChild);})();
That’s it! Now when you mouse in and out of the window it should show and hide an overlay. If you don’t like it just restart the app.