After searching for a while I realized that this error in my Windows 10 64 bits was related to JavaScript. In order to see this go to your browser DevTools and confirm that first. In my case it shows an error like "MIME type ('application/javascript') is not executable".
If that is the case I've found a solution. Here's the deal:
- Borrowing user "ilango100" on https://github.com/jupyterlab/jupyterlab/issues/6098:
I had the exact same issue a while ago. I think this issue is specific to Windows. It is due to the wrong MIME type being set in Windows registry for javascript files. I solved the issue by editing the Windows registry with correct content type:
regedit -> HKEY_LOCAL_MACHINE\Software\Classes -> You will see lot of folders for each file extension -> Just scroll down to ".js" registry and select it -> On the right, if the "Content Type" value is other than application/javascript, then this is causing the problem. Right click on Content Type and change the value to application/javascript
enter image description here
Try again in the browser."
After that I've realized that the error changes. It doesn't even open automatically in the browser anymore. PGAdmin, however, will be open on the side bar (close to the calendar/clock). By trying to open in the browser directly ("New PGAdmin 4 window...") it doesn't work either.
FINAL SOLUTION: click on "Copy server URL" and paste it on your browser. It worked for me!
EDIT: Copying server URL might not be necessary, as explained by Eric Mutta in the comment below.