Since Chrome 83 there is an omnibox-context-menu-show-full-urls
flag that enables showing full URLs in the omnibox.
chrome://flags/#omnibox-context-menu-show-full-urls
- Copy and paste the URL.
- Select Enabled.
- Relaunch the browser.
Now you'll see the full URL in the address bar:

For Chrome 82 and older:
The easiest solution now is to just to download the Suspicious Site Reporter extension from the Chrome Store. And that's it.
As we can see in the source code, the protocol will not get hidden if this extension is installed:

Previously, setting the omnibox-ui-hide-steady-state-url-trivial-subdomains
flag was the easiest way to show the "https://www." back again, but it has been removed as of Chrome 76.

chrome://flags/#omnibox-ui-hide-steady-state-url-trivial-subdomains