There are several solutions out there for when Chromium complains about connection not private. Commonly, you can click advanced and then proceed anyway. However, sometimes there’s a problem with your SSL security certificates. I’ll briefly cover some solutions here.

Date and Time:

Simply check your system’s date and time ala

$ date

specifically, check the year and, if needed correct with

$ timedatectl set-time YYYY-MM-DD

This is probably the most common response if you were to Google “chromium connection not private” or the error code NET:ERR_CERT_COMMON_NAME_INVALID / NET:ERR_CERT_AUTHORITY_INVALID.

While this has worked for me in the past, this was to no avail with my current case. In fact, there was not even a proceed anyway option. So, let’s continue…

Manually Update Certificate:

  1. Click on the certificate warning, it should pop up a lot of information about the certificate.
  2. Highlight the certificate from where it states ---BEGIN CERFICATE--- through the end. Then, copy it to your clipboard.
  3. Paste that to a file such as ~/chromium.crt
  4. $ certutil -d sql:$HOME/.pki/nssdb -A -t P -n chromium_cert -i ~/chromium.crt

  5. Restart chromium

This did work for me. See original solution source on

Adding Self-Signed Certificates:

In a similar vein I decided to go ahead and proceed with this as well.
Afer the above fix, Google app sites and a few others worked fine, but I was still getting the connection not private error fairly frequently.
The procedure for this is clearly laid out in the relevant section of the Arch Wiki dealing with Chromiun Tips / Tricks #SSL certificates.

Savagezen's Blog

A minimalist guide to my many projects.