Unchecked runtime.lastError: The message port closed before a response was received

One posible reason for this is that Google Chrome 73 onward disallows cross-origin requests in content scripts from extensions:

"In Q1 2019, Chrome is removing the ability to make cross-origin requests in content scripts for new and previously unaffected extensions, while maintaining an "allow list" of affected extensions that may continue to make such requests for the time being. This change starts in Chrome 73 (version 73.0.3666.0), which will reach Beta channel around February 7 and Stable channel around March 12. We have identified that less than 1% of Chrome Web Store extensions with more than 1000 users will be affected, only 18 of which are in the top 1000 extensions. The initial allowlist contains around 70 extensions."

See references:

1. https://www.chromium.org/Home/chromium-security/extension-content-script-fetches
2. https://www.chromestatus.com/feature/5629709824032768

You can try to use Chrome in Incognito mode, where extensions are disabled, to see if that's resolved the problem. In normal mode case you can disable extensions one by one via chrome://extensions/ until you find the one causing the problem and disable that one extension.

Thanks Brain,

It was resolved by disabling "Google Publisher Toolbar" extension from chrome browser.