[ubuntu] Network manager - how to apply patch for known bug

I'm currently trying to configure access to my university's network. I'm using TLS authentication with a .cer and .p12 file that I get from my university.

There are two issues I had with Ubuntu 16.04, both of which are apparently known:
1) I caot load the .p12 file and instead must drag and drop the file into the box next to "private-key"
2) I get the error: "Unencrypted private keys are insecure The selected private key does not appear to be protected by a password. This could allow your security credentials to be compromised. Please select a password-protected private key. (You can password-protect your private key with openssl)"

I'm okay with my workaround for #1, but #2 appears to be an a known issue: https://bugs.launchpad.net/network-manager/+bug/1573720.

Furthermore, it seems like there's a fix: https://bugs.launchpad.net/network-m...720/Idea/6

However, I don't know how to apply the fix, which seems to consist of editing libnm-core/nm-utils.c. I caot seem to be able to find/access that directory or file. What steps must I follow in order to apply the known fix?

Thanks,