This extension will color any occurrences of IPv4 or IPv6 addresses.

This extension contributes the following settings:

• highlight-ip.v4: Determines if IPv4 addresses will be highlighted.

• highlight-ip.v6: Determines if IPv6 addresses will be highlighted.

• highlight-ip.cidr: Determines if subnet length (e.g. /24) will be highlighted in addition to the address.

• highlight-ip.strict: Extra validation for proper formatting of IP address (RFC5952 rules for IPv6) and subnet.

"highlight-ip.v4": true,
"highlight-ip.v6": true,
"highlight-ip.cidr": true,
"highlight-ip.strict": false,

This extension contributes the following colors:

• ipaddress.network: Color for IP address.

• ipaddress.subnet: Color for IP subnet length.

• ipaddress.issue: Color for the IP address breaking the rule.

"workbench.colorCustomizations": {
    "ipaddress.network": "textLink.foreground",
    "ipaddress.subnet": "textLink.foreground",
    "ipaddress.issue": "errorForeground",
}

For performance reasons Visual Studio Code doesn't synchronize files that are over 5MB in size (see issue 27100). Therefore, no coloring will be done in large files. To avoid this you can set editor.largeFileOptimizations to false.