How to fix 'Unchecked runtime.lastError: Could not establish connection. Receiving end does not exist.' : <p>I recently uninstalled and reinstalled Postgres10. I then went to run a Node/Express/React application that relies on connecting to a Postgres database (and communicating with it using Sequelize). </p>

<p>Initially it could not connect to the database. I realized the uninstall process removed my old databases, so then I went and re-created a new one with the name that this application connects to. Then when I restarted the app (both server and client), front-end interaction with the database was working again like normal - writing new users and reading them for authentication etc.</p>

<p>However, I now have the following error in the Chrome Dev Tools console on every page-load of the app:</p>

<blockquote>
  <p>Unchecked runtime.lastError: Could not establish connection. Receiving end does not exist</p>
</blockquote>

<p>This error makes a reference to localhost/:1. When I hover over this, it shows <a href="http://localhost:3000/" rel="noreferrer">http://localhost:3000/</a>, the address I'm viewing the app at in the browser.</p>

<p>Anyone have an idea what is going on? Most of the other threads I've found that bring up this error seem to be related to someone trying to develop a Chrome Extension, and even then they tend to have very few responses.</p>
