Sometimes IPv6 protocols can meddle with your connection stability in some MacOS version. You can manually switch it off to improve the connection quality. Here are the instructions you need to follow:

Open Terminal
  1. Open Finder
  2. Choose Applications
  3. Click on “Utilities Folder”
  4. Find and double-click on “Terminal.app”
  5. Run this command in the terminal window: networksetup -listallnetworkservices

You will see all your web connections in a list. You need to identify the one you are using now to proceed. Typically, it will be a Wi-Fi or Ethernet (if an Internet cable is plugged into your PC/laptop).

Disable IPv6

To switch off the IPv6 protocol, type into the terminal window the following command:

networksetup -setv6off Ethernet (for Ethernet interface) or

networksetup -setv6off Wi-Fi (for Wi-Fi interface)

 

The system will ask you to confirm the action by putting in your System Administrator password. After that, the IPv6 will be disabled.

If you need to switch the protocol on again, repeat all the actions above to open the terminal, and then input and run the following commands:

networksetup -setv6automatic Ethernet (for Ethernet interface) or

networksetup -setv6 automatic Wi-Fi (for Wi-Fi interface)

Important note: Any changes to your network preferences may cancel these settings, so you will have to repeat the process again.