{
    "extends": [
      "config:base"
    ],
    "separateMinorPatch": true,
    "separateMajorMinor": true,
    "separateMultipleMajor": true,
    "regexManagers": [
      {
        "fileMatch": ["^.*/?Dockerfile$"],
        "matchStrings": ["^FROM (?<depName>ubuntu):(?<currentValue>[a-zA-Z]+)-(?<build>\\d+)"],
        "depNameTemplate": "{{depName}}",
        "datasourceTemplate": "docker"
      }
    ],
    "packageRules": [
      {
        "datasources": ["docker"],
        "packageNames": ["ubuntu"],
        "allowedVersions": "/^{{majorVersion}}-/"
      }
    ]
  }