We had some reports from clients regarding Slow Performance when using the 'Present'/'Publish' in design mode in Chrome Browsers

We found that the cause was browsers extensions.
As it turns out, Google had changed the chrome extension API, which caused some extensions to break.
These broken extensions throw errors to the console and cause overall slowness.

To resolve,
Turn off all extensions (chrome://extensions/), 
Then close and open the browser

To check if the extensions you need throws errors, turn each on, and click F12 for the Chrome dev tools, then choose the 'Console' tab (if it's not already open on that tab.
 

If you continue to experience performance issues, contact our support team.