Disable a few more rules.

They are valid, but because we have a mix of Hugo shortcodes and Markdown, it's hard to tackle them.

.markdownlint.json

@@ -0,0 +1,30 @@
+{
+  "default": true,
+  "MD001": false,
+  "MD003": {
+    "style": "atx"
+  },
+  "MD004": {
+    "style": "dash"
+  },
+  "MD007": {
+    "indent": 2
+  },
+  "MD012": {
+    "maximum": 2
+  },
+  "MD013": false,
+  "MD022": false,
+  "MD024": false,
+  "MD026": false,
+  "MD032": false,
+  "MD033": false,
+  "MD035": {
+    "style": "---"
+  },
+  "MD036": false,
+  "MD041": false,
+  "MD046": {
+    "style": "fenced"
+  }
+}

package-lock.json

@@ -6531,6 +6531,15 @@
       "integrity": "sha1-HADHQ7QzzQpOgHWPe2SldEDZ/wA=",
       "dev": true
     },
+    "linkify-it": {
+      "version": "3.0.2",
+      "resolved": "https://registry.npmjs.org/linkify-it/-/linkify-it-3.0.2.tgz",
+      "integrity": "sha512-gDBO4aHNZS6coiZCKVhSNh43F9ioIL4JwRjLZPkoLIY4yZFwg264Y5lu2x6rb1Js42Gh6Yqm2f6L2AJcnkzinQ==",
+      "dev": true,
+      "requires": {
+        "uc.micro": "^1.0.1"
+      }
+    },
     "linkinator": {
       "version": "2.2.2",
       "resolved": "https://registry.npmjs.org/linkinator/-/linkinator-2.2.2.tgz",
@@ -6918,6 +6927,27 @@
       "integrity": "sha512-8z4efJYk43E0upd0NbVXwgSTQs6cT3T06etieCMEg7dRbzCbxUCK/GHlX8mhHRDcp+OLlHkPKsvqQTCvsRl2cg==",
       "dev": true
     },
+    "markdown-it": {
+      "version": "11.0.0",
+      "resolved": "https://registry.npmjs.org/markdown-it/-/markdown-it-11.0.0.tgz",
+      "integrity": "sha512-+CvOnmbSubmQFSA9dKz1BRiaSMV7rhexl3sngKqFyXSagoA3fBdJQ8oZWtRy2knXdpDXaBw44euz37DeJQ9asg==",
+      "dev": true,
+      "requires": {
+        "argparse": "^1.0.7",
+        "entities": "~2.0.0",
+        "linkify-it": "^3.0.1",
+        "mdurl": "^1.0.1",
+        "uc.micro": "^1.0.5"
+      },
+      "dependencies": {
+        "entities": {
+          "version": "2.0.3",
+          "resolved": "https://registry.npmjs.org/entities/-/entities-2.0.3.tgz",
+          "integrity": "sha512-MyoZ0jgnLvB2X3Lg5HqpFmn1kybDiIfEQmKzTb5apr51Rb+T3KdmMiqa70T+bhGnyv7bQ6WMj2QMHpGMmlrUYQ==",
+          "dev": true
+        }
+      }
+    },
     "markdown-table": {
       "version": "2.0.0",
       "resolved": "https://registry.npmjs.org/markdown-table/-/markdown-table-2.0.0.tgz",
@@ -6927,6 +6957,87 @@
         "repeat-string": "^1.0.0"
       }
     },
+    "markdownlint": {
+      "version": "0.21.1",
+      "resolved": "https://registry.npmjs.org/markdownlint/-/markdownlint-0.21.1.tgz",
+      "integrity": "sha512-8kc88w5dyEzlmOWIElp8J17qBgzouOQfJ0LhCcpBFrwgyYK6JTKvILsk4FCEkiNqHkTxwxopT2RS2DYb/10qqg==",
+      "dev": true,
+      "requires": {
+        "markdown-it": "11.0.0"
+      }
+    },
+    "markdownlint-cli2": {
+      "version": "0.0.11",
+      "resolved": "https://registry.npmjs.org/markdownlint-cli2/-/markdownlint-cli2-0.0.11.tgz",
+      "integrity": "sha512-+dwVrLo2sisB8OJE8vdT+gTQCOuaYFJsYKKfh1fnkHedSMxVrX6XMID5kUKI7iSq6GICugPnS5kjjVwCbe01vg==",
+      "dev": true,
+      "requires": {
+        "globby": "~11.0.1",
+        "markdownlint": "~0.21.1",
+        "markdownlint-cli2-formatter-default": "~0.0.1",
+        "markdownlint-rule-helpers": "~0.12.0",
+        "micromatch": "~4.0.2",
+        "strip-json-comments": "~3.1.1",
+        "yaml": "~1.10.0"
+      },
+      "dependencies": {
+        "braces": {
+          "version": "3.0.2",
+          "resolved": "https://registry.npmjs.org/braces/-/braces-3.0.2.tgz",
+          "integrity": "sha512-b8um+L1RzM3WDSzvhm6gIz1yfTbBt6YTlcEKAvsmqCZZFw46z626lVj9j1yEPW33H5H+lBQpZMP1k8l+78Ha0A==",
+          "dev": true,
+          "requires": {
+            "fill-range": "^7.0.1"
+          }
+        },
+        "fill-range": {
+          "version": "7.0.1",
+          "resolved": "https://registry.npmjs.org/fill-range/-/fill-range-7.0.1.tgz",
+          "integrity": "sha512-qOo9F+dMUmC2Lcb4BbVvnKJxTPjCm+RRpe4gDuGrzkL7mEVl/djYSu2OdQ2Pa302N4oqkSg9ir6jaLWJ2USVpQ==",
+          "dev": true,
+          "requires": {
+            "to-regex-range": "^5.0.1"
+          }
+        },
+        "is-number": {
+          "version": "7.0.0",
+          "resolved": "https://registry.npmjs.org/is-number/-/is-number-7.0.0.tgz",
+          "integrity": "sha512-41Cifkg6e8TylSpdtTpeLVMqvSBEVzTttHvERD741+pnZ8ANv0004MRL43QKPDlK9cGvNp6NZWZUBlbGXYxxng==",
+          "dev": true
+        },
+        "micromatch": {
+          "version": "4.0.2",
+          "resolved": "https://registry.npmjs.org/micromatch/-/micromatch-4.0.2.tgz",
+          "integrity": "sha512-y7FpHSbMUMoyPbYUSzO6PaZ6FyRnQOpHuKwbo1G+Knck95XVU4QAiKdGEnj5wwoS7PlOgthX/09u5iFJ+aYf5Q==",
+          "dev": true,
+          "requires": {
+            "braces": "^3.0.1",
+            "picomatch": "^2.0.5"
+          }
+        },
+        "to-regex-range": {
+          "version": "5.0.1",
+          "resolved": "https://registry.npmjs.org/to-regex-range/-/to-regex-range-5.0.1.tgz",
+          "integrity": "sha512-65P7iz6X5yEr1cwcgvQxbbIw7Uk3gOy5dIdtZ4rDveLqhrdJP+Li/Hx6tyK0NEb+2GCyneCMJiGqrADCSNk8sQ==",
+          "dev": true,
+          "requires": {
+            "is-number": "^7.0.0"
+          }
+        }
+      }
+    },
+    "markdownlint-cli2-formatter-default": {
+      "version": "0.0.1",
+      "resolved": "https://registry.npmjs.org/markdownlint-cli2-formatter-default/-/markdownlint-cli2-formatter-default-0.0.1.tgz",
+      "integrity": "sha512-JvWhlus5zR4cFywXB2RSPVX73YD9177xm9WkV/8CRPDS1MM/Fh6Ds0WnY67ZaiITavZ0H+Fgz1aVhUwrPNa7ug==",
+      "dev": true
+    },
+    "markdownlint-rule-helpers": {
+      "version": "0.12.0",
+      "resolved": "https://registry.npmjs.org/markdownlint-rule-helpers/-/markdownlint-rule-helpers-0.12.0.tgz",
+      "integrity": "sha512-Q7qfAk+AJvx82ZY52OByC4yjoQYryOZt6D8TKrZJIwCfhZvcj8vCQNuwDqILushtDBTvGFmUPq+uhOb1KIMi6A==",
+      "dev": true
+    },
     "mathml-tag-names": {
       "version": "2.1.3",
       "resolved": "https://registry.npmjs.org/mathml-tag-names/-/mathml-tag-names-2.1.3.tgz",
@@ -6942,6 +7053,12 @@
         "unist-util-visit": "^2.0.0"
       }
     },
+    "mdurl": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/mdurl/-/mdurl-1.0.1.tgz",
+      "integrity": "sha1-/oWy7HWlkDfyrf7BAP1sYBdhFS4=",
+      "dev": true
+    },
     "media-typer": {
       "version": "0.3.0",
       "resolved": "https://registry.npmjs.org/media-typer/-/media-typer-0.3.0.tgz",
@@ -11161,6 +11278,12 @@
       "integrity": "sha512-YUxzMjJ5T71w6a8WWVcMGM6YWOTX27rCoIQgLXiWaxqXSx9D7DNjiGWn1aJIRSQ5qr0xuhra77bSIh6voR/46Q==",
       "dev": true
     },
+    "uc.micro": {
+      "version": "1.0.6",
+      "resolved": "https://registry.npmjs.org/uc.micro/-/uc.micro-1.0.6.tgz",
+      "integrity": "sha512-8Y75pvTYkLJW2hWQHXxoqRgV7qb9B+9vFEtidML+7koHUFapnVJAZ6cKs+Qjz5Aw3aZWHMC6u0wJE3At+nSGwA==",
+      "dev": true
+    },
     "unbzip2-stream": {
       "version": "1.4.3",
       "resolved": "https://registry.npmjs.org/unbzip2-stream/-/unbzip2-stream-1.4.3.tgz",

package.json

@@ -51,8 +51,9 @@
     "docs-build": "hugo --cleanDestinationDir",
     "docs-compile": "npm run docs-build",
     "docs-linkinator": "linkinator _gh_pages --recurse --silent --skip \"^(?!http://localhost)\"",
+    "docs-markdownlint": "markdownlint-cli2 \"**/*.md\" \"!**/node_modules/**\"",
     "docs-vnu": "node build/vnu-jar.js",
-    "docs-lint": "npm-run-all --parallel docs-vnu docs-linkinator",
+    "docs-lint": "npm-run-all --parallel docs-markdownlint docs-vnu docs-linkinator",
     "docs-serve": "hugo server --port 9001 --disableFastRender",
     "docs-serve-only": "npx sirv-cli _gh_pages --port 9001",
     "lockfile-lint": "lockfile-lint --allowed-hosts npm --allowed-schemes https: --empty-hostname false --type npm --path package-lock.json",
@@ -123,6 +124,7 @@
     "karma-rollup-preprocessor": "^7.0.5",
     "linkinator": "^2.2.2",
     "lockfile-lint": "^4.3.7",
+    "markdownlint-cli2": "0.0.11",
     "nodemon": "^2.0.6",
     "npm-run-all": "^4.1.5",
     "popper.js": "^1.16.1",