diff --git a/__tests__/helpers/fileReader.ts b/__tests__/helpers/fileReader.ts
new file mode 100644
index 0000000000000000000000000000000000000000..65c2653f1c6bffd1480ef5fbab0f6e28cac892f6
--- /dev/null
+++ b/__tests__/helpers/fileReader.ts
@@ -0,0 +1,16 @@
+const fs = require("fs");
+
+export const listDirectories = (testCasesPath: string): Array<string> => {
+  return fs.readdirSync(testCasesPath).filter(function (file) {
+    return fs.statSync(testCasesPath + "/" + file).isDirectory();
+  });
+};
+
+const filesCache: { [key: string]: string } = {};
+export const readFile = (path: string): string => {
+  if (!filesCache[path]) {
+    filesCache[path] = fs.readFileSync(path).toString();
+  }
+
+  return filesCache[path];
+};
diff --git a/__tests__/helpers/index.ts b/__tests__/helpers/index.ts
new file mode 100644
index 0000000000000000000000000000000000000000..4b52c948578d04983f18fecaf4953c63378e6262
--- /dev/null
+++ b/__tests__/helpers/index.ts
@@ -0,0 +1,245 @@
+import { JSDOM } from "jsdom";
+const crypto = require("crypto");
+import MIMEParser from "@vereign/mime-parser";
+import { expect, test } from "@jest/globals";
+import { DOM } from "@vereign/dom";
+
+import { PlainNormalizer, HTMLNormalizer } from "../../src";
+import { listDirectories, readFile } from "./fileReader";
+import { diffStringsUnified } from "jest-diff";
+
+const SENT_EML_NAME = "sent.eml";
+const RECEIVED_EML_NAME = "received.eml";
+
+/**
+ * Substitutes cid:* with base64 strings of the corresponding attachments
+ */
+const POPULATE_ATTACHMENTS = true;
+
+interface CasesFilteringOptions {
+  ignore?: string[];
+  checkExclusively?: string[];
+}
+
+/**
+ * Hashes base64 of the attachments to improve performance and readability
+ * @param base64
+ */
+const hashAttachment = (base64: string) => {
+  return crypto
+    .createHash("sha256")
+    .update(Buffer.from(base64, "base64"))
+    .digest()
+    .toString("base64");
+};
+
+expect.extend({
+  /**
+   * Extends "toEqual" with diff functionality
+   */
+  toEqualWithDiff(target, source) {
+    let pass = true;
+    try {
+      expect(target).toEqual(source);
+    } catch (e) {
+      pass = false;
+    }
+
+    return {
+      pass,
+      message: pass ? () => "Pass" : () => diffStringsUnified(source, target),
+    };
+  },
+});
+
+export const createDescribeHtmlTestCases = (
+  testsPath: string,
+  vendor: string
+) => (
+  casesGroupName: string,
+  filteringOptions?: CasesFilteringOptions
+) => (): void => {
+  const testCases = prepareTestCases(
+    testsPath,
+    casesGroupName,
+    filteringOptions
+  );
+
+  test.concurrent.each(testCases)(
+    "Case %s",
+    async (dirName, { sentMime, receivedMime }) => {
+      const { sentHtmlDocument, receivedHtmlDocument } = await getDOMDocuments(
+        sentMime,
+        receivedMime
+      );
+
+      const sentHtml = HTMLNormalizer.normalizeVendorHtml(
+        sentHtmlDocument,
+        vendor
+      );
+      const receivedHtml = HTMLNormalizer.normalizeVendorHtml(
+        receivedHtmlDocument,
+        vendor
+      );
+
+      // eslint-disable-next-line
+      // @ts-ignore
+      expect(receivedHtml).toEqualWithDiff(sentHtml);
+    }
+  );
+};
+
+export const createDescribePlainTestCases = (testsPath: string) => (
+  casesGroupName: string,
+  filteringOptions?: CasesFilteringOptions
+) => (): void => {
+  const testCases = prepareTestCases(
+    testsPath,
+    casesGroupName,
+    filteringOptions
+  );
+
+  test.concurrent.each(testCases)(
+    "Case %s",
+    async (dirName, { sentMime, receivedMime }) => {
+      const sentNormalizedPlain = PlainNormalizer.normalizePlain(
+        await sentMime.getPlain({
+          populateAttachments: POPULATE_ATTACHMENTS,
+          hashAttachment,
+        })
+      );
+      const receivedNormalizedPlain = PlainNormalizer.normalizePlain(
+        await receivedMime.getPlain({
+          populateAttachments: POPULATE_ATTACHMENTS,
+          hashAttachment,
+        })
+      );
+
+      // eslint-disable-next-line
+      // @ts-ignore
+      expect(receivedNormalizedPlain).toEqualWithDiff(sentNormalizedPlain);
+    }
+  );
+};
+
+export const createDescribePseudoPlainTestCases = (
+  testsPath: string,
+  vendor: string
+) => (
+  casesGroupName: string,
+  filteringOptions?: CasesFilteringOptions
+) => (): void => {
+  const testCases = prepareTestCases(
+    testsPath,
+    casesGroupName,
+    filteringOptions
+  );
+
+  test.concurrent.each(testCases)(
+    "Case %s",
+    async (dirName, { sentMime, receivedMime }) => {
+      const { sentHtmlDocument, receivedHtmlDocument } = await getDOMDocuments(
+        sentMime,
+        receivedMime
+      );
+
+      HTMLNormalizer.normalizeVendorHtml(sentHtmlDocument, vendor);
+      HTMLNormalizer.normalizeVendorHtml(receivedHtmlDocument, vendor);
+
+      const normalizedSentPseudoPlainText = HTMLNormalizer.extractPseudoPlainPart(
+        sentHtmlDocument
+      );
+
+      const normalizedReceivedPseudoPlainText = HTMLNormalizer.extractPseudoPlainPart(
+        receivedHtmlDocument
+      );
+
+      // eslint-disable-next-line
+      // @ts-ignore
+      expect(normalizedReceivedPseudoPlainText).toEqualWithDiff(
+        normalizedSentPseudoPlainText
+      );
+    }
+  );
+};
+
+const prepareTestCases = (
+  path: string,
+  casesGroup: string,
+  filteringOptions: CasesFilteringOptions
+): Array<[string, { sentMime: MIMEParser; receivedMime: MIMEParser }]> => {
+  const testsCasesPath = path + "/" + casesGroup;
+  const casesDirs = listDirectories(testsCasesPath);
+  const casesDirsFiltered = filterTestCases(casesDirs, filteringOptions);
+
+  return casesDirsFiltered.map((caseDir) => {
+    const sentMimeString = readFile(
+      `${testsCasesPath}/${caseDir}/${SENT_EML_NAME}`
+    );
+    const receivedMimeString = readFile(
+      `${testsCasesPath}/${caseDir}/${RECEIVED_EML_NAME}`
+    );
+
+    return [
+      caseDir,
+      {
+        sentMime: new MIMEParser(sentMimeString),
+        receivedMime: new MIMEParser(receivedMimeString),
+      },
+    ];
+  });
+};
+
+/**
+ *
+ * @param {Array<string>} casesNames
+ * @param {Object} options
+ * @param {Array<string>}  options.ignore - ignores specific test cases
+ * @param {Array<string>}  options.checkExclusively - focuses on specific test cases (disregards toIgnore)
+ */
+const filterTestCases = (
+  casesNames: string[],
+  options: CasesFilteringOptions
+): string[] => {
+  const ignore = options?.ignore;
+  const checkExclusively = options?.checkExclusively;
+
+  if (checkExclusively?.length) {
+    return casesNames.filter((caseName) => checkExclusively.includes(caseName));
+  }
+
+  if (ignore?.length) {
+    return casesNames.filter((caseName) => !ignore.includes(caseName));
+  }
+
+  return casesNames;
+};
+
+export const getDOMDocuments = async (
+  sentMime: MIMEParser,
+  receivedMime: MIMEParser
+): Promise<{
+  sentHtmlDocument: HTMLDocument;
+  receivedHtmlDocument: HTMLDocument;
+}> => {
+  /**
+   * Usage of the @vereign/dom is a must, because of Google Add-on.
+   */
+  const sentDOM = new DOM(
+    await sentMime.getHTML({
+      populateAttachments: POPULATE_ATTACHMENTS,
+      hashAttachment,
+    })
+  );
+  const receivedDOM = new JSDOM(
+    await receivedMime.getHTML({
+      populateAttachments: POPULATE_ATTACHMENTS,
+      hashAttachment,
+    })
+  );
+
+  return {
+    sentHtmlDocument: sentDOM.window.document,
+    receivedHtmlDocument: receivedDOM.window.document,
+  };
+};
diff --git a/__tests__/html-gmail-gmail.test.ts b/__tests__/html-gmail-gmail.test.ts
index bb4fa7a3e58a07ee640965e9f0c6a3799d6f4690..f12591d843558467866627d13c06068dec7ebe2f 100644
--- a/__tests__/html-gmail-gmail.test.ts
+++ b/__tests__/html-gmail-gmail.test.ts
@@ -2,16 +2,13 @@ import { EMAIL_VENDORS } from "../src";
 
 const path = require("path");
 import { describe } from "@jest/globals";
-import { createDescribeHtmlTestCases } from "./utils";
+import { createDescribeHtmlTestCases } from "./helpers";
 
 const TESTS_GLOBAL_PATH = "/files/gmail-gmail";
 const testsPath = path.resolve(__dirname, `.${TESTS_GLOBAL_PATH}`);
 
 describe("[HTML] GMail-GMail", () => {
-  const describeFunction = createDescribeHtmlTestCases(
-    testsPath,
-    EMAIL_VENDORS.GMAIL
-  );
+  const runTests = createDescribeHtmlTestCases(testsPath, EMAIL_VENDORS.GMAIL);
 
-  describe("Chrome-Chrome", describeFunction("chrome-chrome", [""]));
+  describe("Chrome-Chrome", runTests("chrome-chrome", {}));
 });
diff --git a/__tests__/html-gmail-outlook.test.ts b/__tests__/html-gmail-outlook.test.ts
index 0f214527ac0011f1f9b422a5368dad452c407dff..884c87b53ad8b8421074eba9def4576a53b08f8b 100644
--- a/__tests__/html-gmail-outlook.test.ts
+++ b/__tests__/html-gmail-outlook.test.ts
@@ -2,16 +2,13 @@ import { EMAIL_VENDORS } from "../src";
 
 const path = require("path");
 import { describe } from "@jest/globals";
-import { createDescribeHtmlTestCases } from "./utils";
+import { createDescribeHtmlTestCases } from "./helpers";
 
 const TESTS_GLOBAL_PATH = "/files/gmail-outlook";
 const testsPath = path.resolve(__dirname, `.${TESTS_GLOBAL_PATH}`);
 
 describe("[HTML] GMail-Outlook", () => {
-  const describeFunction = createDescribeHtmlTestCases(
-    testsPath,
-    EMAIL_VENDORS.GMAIL
-  );
+  const runTests = createDescribeHtmlTestCases(testsPath, EMAIL_VENDORS.GMAIL);
 
-  describe("Chrome-Chrome", describeFunction("chrome-chrome", [""]));
+  describe("Chrome-Chrome", runTests("chrome-chrome"));
 });
diff --git a/__tests__/html-outlook-gmail.test.ts b/__tests__/html-outlook-gmail.test.ts
index c0e8ad88283b0d459321ec0c67fd1e4a39d6f048..ebb0feba821d267b7e7edec955fb388bc7175d96 100644
--- a/__tests__/html-outlook-gmail.test.ts
+++ b/__tests__/html-outlook-gmail.test.ts
@@ -1,16 +1,16 @@
 import { describe } from "@jest/globals";
 import { EMAIL_VENDORS } from "../src";
-import { createDescribeHtmlTestCases } from "./utils";
+import { createDescribeHtmlTestCases } from "./helpers";
 const path = require("path");
 
 const TESTS_GLOBAL_PATH = "/files/outlook-gmail";
 const testsPath = path.resolve(__dirname, `.${TESTS_GLOBAL_PATH}`);
 
 describe("[HTML] Outlook-GMail emails normalization", () => {
-  const describeFunction = createDescribeHtmlTestCases(
+  const runTests = createDescribeHtmlTestCases(
     testsPath,
     EMAIL_VENDORS.OUTLOOK
   );
 
-  describe("Chrome-Chrome", describeFunction("chrome-chrome", []));
+  describe("Chrome-Chrome", runTests("chrome-chrome"));
 });
diff --git a/__tests__/html-outlook-outlook.test.ts b/__tests__/html-outlook-outlook.test.ts
index 684848daa2439887e34b77253611cda61f16b632..f27a85e6d84420c60423610a170269f8752136ca 100644
--- a/__tests__/html-outlook-outlook.test.ts
+++ b/__tests__/html-outlook-outlook.test.ts
@@ -1,24 +1,24 @@
 import { describe } from "@jest/globals";
 import { EMAIL_VENDORS } from "../src";
-import { createDescribeHtmlTestCases } from "./utils";
+import { createDescribeHtmlTestCases } from "./helpers";
 const path = require("path");
 
 const TESTS_GLOBAL_PATH = "/files/outlook-outlook";
 const testsPath = path.resolve(__dirname, `.${TESTS_GLOBAL_PATH}`);
 
 describe("[HTML] Outlook-Outlook emails normalization", () => {
-  const describeFunction = createDescribeHtmlTestCases(
+  const runTests = createDescribeHtmlTestCases(
     testsPath,
     EMAIL_VENDORS.OUTLOOK
   );
 
-  describe("Chrome-Chrome", describeFunction("chrome-chrome", [], []));
+  describe("Chrome-Chrome", runTests("chrome-chrome"));
   describe(
     "MacOS-MacOS",
-    describeFunction("macos-macos", ["03", "04", "05", "08", "09"])
+    runTests("macos-macos", { ignore: ["03", "04", "05", "08", "09"] })
   );
   describe(
     "Windows-Windows",
-    describeFunction("windows-windows", ["11", "12", "13", "16"])
+    runTests("windows-windows", { ignore: ["11", "12", "13", "16"] })
   );
 });
diff --git a/__tests__/htmltext-gmail-gmail.test.ts b/__tests__/htmltext-gmail-gmail.test.ts
index a23c2de1c1eed2c585f0b6dff6c47df53c75cb8a..b6d98b16baa311a39332dd9af819cb1150d9b177 100644
--- a/__tests__/htmltext-gmail-gmail.test.ts
+++ b/__tests__/htmltext-gmail-gmail.test.ts
@@ -2,16 +2,16 @@ import { EMAIL_VENDORS } from "../src";
 
 const path = require("path");
 import { describe } from "@jest/globals";
-import { createDescribePseudoPlainTestCases } from "./utils";
+import { createDescribePseudoPlainTestCases } from "./helpers";
 
 const TESTS_GLOBAL_PATH = "/files/gmail-gmail";
 const testsPath = path.resolve(__dirname, `.${TESTS_GLOBAL_PATH}`);
 
 describe("[Pseudo PLAIN] GMail-GMail", () => {
-  const describeFunction = createDescribePseudoPlainTestCases(
+  const runTests = createDescribePseudoPlainTestCases(
     testsPath,
     EMAIL_VENDORS.GMAIL
   );
 
-  describe("Gmail-Gmail", describeFunction("chrome-chrome"));
+  describe("Gmail-Gmail", runTests("chrome-chrome"));
 });
diff --git a/__tests__/htmltext-gmail-outlook.test.ts b/__tests__/htmltext-gmail-outlook.test.ts
index 47bc081233251df2045ced8a3927b207609adb92..c05314d428087fa7f28402a8acc00fcf010a0f1e 100644
--- a/__tests__/htmltext-gmail-outlook.test.ts
+++ b/__tests__/htmltext-gmail-outlook.test.ts
@@ -1,5 +1,5 @@
 import { describe } from "@jest/globals";
-import { createDescribePseudoPlainTestCases } from "./utils";
+import { createDescribePseudoPlainTestCases } from "./helpers";
 import { EMAIL_VENDORS } from "../src";
 const path = require("path");
 
@@ -8,9 +8,9 @@ const TESTS_GLOBAL_PATH = "/files/gmail-outlook";
 const testsPath = path.resolve(__dirname, `.${TESTS_GLOBAL_PATH}`);
 
 describe("[Pseudo PLAIN] Gmail-Outlook normalization", () => {
-  const describeFunction = createDescribePseudoPlainTestCases(
+  const runTests = createDescribePseudoPlainTestCases(
     testsPath,
     EMAIL_VENDORS.GMAIL
   );
-  describe("Chrome-Chrome", describeFunction("chrome-chrome"));
+  describe("Chrome-Chrome", runTests("chrome-chrome"));
 });
diff --git a/__tests__/htmltext-outlook-gmail.test.ts b/__tests__/htmltext-outlook-gmail.test.ts
index 08384831c2eaa9571988e89db1464f8e450aa73a..ce451f25193b5a0fe3e8e8209ccc682a5c970af8 100644
--- a/__tests__/htmltext-outlook-gmail.test.ts
+++ b/__tests__/htmltext-outlook-gmail.test.ts
@@ -1,5 +1,5 @@
 import { describe } from "@jest/globals";
-import { createDescribePseudoPlainTestCases } from "./utils";
+import { createDescribePseudoPlainTestCases } from "./helpers";
 import { EMAIL_VENDORS } from "../src";
 
 const path = require("path");
@@ -8,11 +8,11 @@ const TESTS_GLOBAL_PATH = "/files/outlook-gmail";
 const testsPath = path.resolve(__dirname, `.${TESTS_GLOBAL_PATH}`);
 
 describe("[Pseudo PLAIN] Outlook-Gmail normalization", () => {
-  const describeFunction = createDescribePseudoPlainTestCases(
+  const runTests = createDescribePseudoPlainTestCases(
     testsPath,
     EMAIL_VENDORS.OUTLOOK
   );
 
   // ["01"] - is a filter. Pass here names of directories with test cases you want to check
-  describe("Chrome-Chrome", describeFunction("chrome-chrome"));
+  describe("Chrome-Chrome", runTests("chrome-chrome"));
 });
diff --git a/__tests__/htmltext-outlook-outlook.test.ts b/__tests__/htmltext-outlook-outlook.test.ts
index 0e2a9ad002316a7451cb1e5e5dd3187e3c0023ba..6d8bc5c31e70ee044882cd5d9e9c610f27b69f3e 100644
--- a/__tests__/htmltext-outlook-outlook.test.ts
+++ b/__tests__/htmltext-outlook-outlook.test.ts
@@ -1,5 +1,5 @@
 import { describe } from "@jest/globals";
-import { createDescribePseudoPlainTestCases } from "./utils";
+import { createDescribePseudoPlainTestCases } from "./helpers";
 import { EMAIL_VENDORS } from "../src";
 
 const path = require("path");
@@ -8,18 +8,18 @@ const TESTS_GLOBAL_PATH = "/files/outlook-outlook";
 const testsPath = path.resolve(__dirname, `.${TESTS_GLOBAL_PATH}`);
 
 describe("[Pseudo PLAIN] Outlook-Outlook normalization", () => {
-  const describeFunction = createDescribePseudoPlainTestCases(
+  const runTests = createDescribePseudoPlainTestCases(
     testsPath,
     EMAIL_VENDORS.OUTLOOK
   );
 
-  describe("Chrome-Chrome", describeFunction("chrome-chrome"));
+  describe("Chrome-Chrome", runTests("chrome-chrome"));
   describe(
     "MacOS-MacOS",
-    describeFunction("macos-macos", ["03", "04", "05", "08", "09"])
+    runTests("macos-macos", { ignore: ["03", "04", "05", "08", "09"] })
   );
   describe(
     "Windows-Windows",
-    describeFunction("windows-windows", ["11", "12", "16"])
+    runTests("windows-windows", { ignore: ["11", "12", "16"] })
   );
 });
diff --git a/__tests__/plain-gmail-gmail.test.ts b/__tests__/plain-gmail-gmail.test.ts
index 33b9954f25323ea55bff2114a8b2b44c9c48b309..7846313571fbb69aac70a7f9c52f89c277f1ab05 100644
--- a/__tests__/plain-gmail-gmail.test.ts
+++ b/__tests__/plain-gmail-gmail.test.ts
@@ -1,12 +1,12 @@
 const path = require("path");
 import { describe } from "@jest/globals";
-import { createDescribePlainTestCases } from "./utils";
+import { createDescribePlainTestCases } from "./helpers";
 
 const TESTS_GLOBAL_PATH = "/files/gmail-gmail";
 const testsPath = path.resolve(__dirname, `.${TESTS_GLOBAL_PATH}`);
 
 describe("[Plain] GMail-GMail", () => {
-  const describeFunction = createDescribePlainTestCases(testsPath);
+  const runTests = createDescribePlainTestCases(testsPath);
 
-  describe("Chrome-Chrome", describeFunction("chrome-chrome", []));
+  describe("Chrome-Chrome", runTests("chrome-chrome"));
 });
diff --git a/__tests__/plain-gmail-outlook.test.ts b/__tests__/plain-gmail-outlook.test.ts
index d15505aafc861bc0a380af8b1e99c941507abcee..47295e16cca772ff7a28e54b439493b4da7c289c 100644
--- a/__tests__/plain-gmail-outlook.test.ts
+++ b/__tests__/plain-gmail-outlook.test.ts
@@ -1,5 +1,5 @@
 import { describe } from "@jest/globals";
-import { createDescribePlainTestCases } from "./utils";
+import { createDescribePlainTestCases } from "./helpers";
 const path = require("path");
 
 const TESTS_GLOBAL_PATH = "/files/gmail-outlook";
@@ -7,6 +7,6 @@ const TESTS_GLOBAL_PATH = "/files/gmail-outlook";
 const testsPath = path.resolve(__dirname, `.${TESTS_GLOBAL_PATH}`);
 
 describe("[Plain] Gmail-Outlook normalization", () => {
-  const describeFunction = createDescribePlainTestCases(testsPath);
-  describe("Chrome-Chrome", describeFunction("chrome-chrome", [], []));
+  const runTests = createDescribePlainTestCases(testsPath);
+  describe("Chrome-Chrome", runTests("chrome-chrome"));
 });
diff --git a/__tests__/plain-outlook-gmail.test.ts b/__tests__/plain-outlook-gmail.test.ts
index f74daacf5c16a94c018e0e2f7c751addbecf185d..ea3c7c98cbce9e84e6dc1d92107b5cde88c1a9c8 100644
--- a/__tests__/plain-outlook-gmail.test.ts
+++ b/__tests__/plain-outlook-gmail.test.ts
@@ -1,5 +1,5 @@
 import { describe } from "@jest/globals";
-import { createDescribePlainTestCases } from "./utils";
+import { createDescribePlainTestCases } from "./helpers";
 const path = require("path");
 
 const TESTS_GLOBAL_PATH = "/files/outlook-gmail";
@@ -7,6 +7,6 @@ const TESTS_GLOBAL_PATH = "/files/outlook-gmail";
 const testsPath = path.resolve(__dirname, `.${TESTS_GLOBAL_PATH}`);
 
 describe("[Plain] Outlook-Gmail normalization", () => {
-  const describeFunction = createDescribePlainTestCases(testsPath);
-  describe("Chrome-Chrome", describeFunction("chrome-chrome"));
+  const runTests = createDescribePlainTestCases(testsPath);
+  describe("Chrome-Chrome", runTests("chrome-chrome"));
 });
diff --git a/__tests__/plain-outlook-outlook.test.ts b/__tests__/plain-outlook-outlook.test.ts
index 335a692e80ef15688f444b37deea6837ecbb54ae..fa6cd546461ca9a795f119cca8f1abba370423a5 100644
--- a/__tests__/plain-outlook-outlook.test.ts
+++ b/__tests__/plain-outlook-outlook.test.ts
@@ -1,5 +1,5 @@
 import { describe } from "@jest/globals";
-import { createDescribePlainTestCases } from "./utils";
+import { createDescribePlainTestCases } from "./helpers";
 const path = require("path");
 
 const TESTS_GLOBAL_PATH = "/files/outlook-outlook";
@@ -7,20 +7,13 @@ const TESTS_GLOBAL_PATH = "/files/outlook-outlook";
 const testsPath = path.resolve(__dirname, `.${TESTS_GLOBAL_PATH}`);
 
 describe("[Plain] Outlook-Outlook normalization", () => {
-  const describeFunction = createDescribePlainTestCases(testsPath);
-  describe("Chrome-Chrome", describeFunction("chrome-chrome"));
-  describe("MacOS-MacOS", describeFunction("macos-macos"));
+  const runTests = createDescribePlainTestCases(testsPath);
+  describe("Chrome-Chrome", runTests("chrome-chrome"));
+  describe("MacOS-MacOS", runTests("macos-macos"));
   describe(
     "Windows-Windows",
-    describeFunction("windows-windows", [
-      "09",
-      "10",
-      "11",
-      "12",
-      "13",
-      "14",
-      "15",
-      "16",
-    ])
+    runTests("windows-windows", {
+      ignore: ["09", "10", "11", "12", "13", "14", "15", "16"],
+    })
   );
 });
diff --git a/__tests__/utils.ts b/__tests__/utils.ts
deleted file mode 100644
index 1ec1507b68cd23acd294d495c67a363b959de6df..0000000000000000000000000000000000000000
--- a/__tests__/utils.ts
+++ /dev/null
@@ -1,269 +0,0 @@
-import { JSDOM } from "jsdom";
-const fs = require("fs");
-const crypto = require("crypto");
-import MIMEParser from "@vereign/mime-parser";
-import { expect, test } from "@jest/globals";
-import { DOM } from "@vereign/dom";
-import { diffStringsUnified } from "jest-diff";
-
-import { PlainNormalizer, HTMLNormalizer } from "../src";
-
-const SENT_EML_NAME = "sent.eml";
-const RECEIVED_EML_NAME = "received.eml";
-
-const populateAttachments = true;
-const hashAttachment = (base64: string) => {
-  return crypto
-    .createHash("sha256")
-    .update(Buffer.from(base64, "base64"))
-    .digest()
-    .toString("base64");
-};
-
-expect.extend({
-  toEqualWithDiff(target, source) {
-    let pass = true;
-    try {
-      expect(target).toEqual(source);
-    } catch (e) {
-      pass = false;
-    }
-
-    return {
-      pass,
-      message: pass ? () => "Pass" : () => diffStringsUnified(source, target),
-    };
-  },
-});
-
-const mimeCache: { [key: string]: MIMEParser } = {};
-const getMime = (path: string): MIMEParser => {
-  if (!mimeCache[path]) {
-    const mimeString = fs.readFileSync(path).toString();
-    mimeCache[path] = new MIMEParser(mimeString);
-  }
-
-  return mimeCache[path];
-};
-
-export const getNormalizedPlain = async (
-  testCasePath: string
-): Promise<{
-  sentPlain: string;
-  receivedPlain: string;
-}> => {
-  const sentMime = getMime(`${testCasePath}/${SENT_EML_NAME}`);
-  const receivedMime = getMime(`${testCasePath}/${RECEIVED_EML_NAME}`);
-
-  const sentNormalizedPlain = PlainNormalizer.normalizePlain(
-    await sentMime.getPlain({
-      populateAttachments,
-      hashAttachment,
-    })
-  );
-  const receivedNormalizedPlain = PlainNormalizer.normalizePlain(
-    await receivedMime.getPlain({
-      populateAttachments,
-      hashAttachment,
-    })
-  );
-
-  return {
-    sentPlain: sentNormalizedPlain,
-    receivedPlain: receivedNormalizedPlain,
-  };
-};
-
-export const getTestCasesDirs = (testCasesPath: string): Array<string> => {
-  return fs.readdirSync(testCasesPath).filter(function (file) {
-    return fs.statSync(testCasesPath + "/" + file).isDirectory();
-  });
-};
-
-export const getNormalizedHtml = async (
-  testCasePath: string,
-  vendor: string
-): Promise<{
-  sentHtml: string;
-  receivedHtml: string;
-}> => {
-  const sentMime = getMime(`${testCasePath}/${SENT_EML_NAME}`);
-  const receivedMime = getMime(`${testCasePath}/${RECEIVED_EML_NAME}`);
-
-  const sentHtml = await sentMime.getHTML({
-    populateAttachments,
-    hashAttachment,
-  });
-  const receivedHtml = await receivedMime.getHTML({
-    populateAttachments,
-    hashAttachment,
-  });
-
-  const sentDOM = new DOM(sentHtml);
-  const receivedDOM = new JSDOM(receivedHtml);
-
-  const sentNormalizedHtml = HTMLNormalizer.normalizeVendorHtml(
-    sentDOM.window.document,
-    vendor
-  );
-  const receivedNormalizedHtml = HTMLNormalizer.normalizeVendorHtml(
-    receivedDOM.window.document,
-    vendor
-  );
-
-  return {
-    sentHtml: sentNormalizedHtml,
-    receivedHtml: receivedNormalizedHtml,
-  };
-};
-
-export const createDescribeHtmlTestCases = (
-  testsPath: string,
-  vendor: string
-) =>
-  /**
-   * @param casesGroupName - name of the folder with cases
-   * @param failingCases - a list of cases that are failing and ignored. Pending to be fixed
-   * @param casesToCheckOnly - a filter to use if you want to check specific cases
-   */
-  (
-    casesGroupName: string,
-    failingCases?: Array<string>,
-    casesToCheckOnly?: Array<string>
-  ) => (): void => {
-    const testsCasesPath = testsPath + "/" + casesGroupName;
-    let testCasesDirs = getTestCasesDirs(testsCasesPath);
-
-    if (casesToCheckOnly && casesToCheckOnly.length) {
-      testCasesDirs = testCasesDirs.filter((dir) =>
-        casesToCheckOnly.includes(dir)
-      );
-    }
-
-    if (failingCases && failingCases.length) {
-      testCasesDirs = testCasesDirs.filter(
-        (dir) => !failingCases.includes(dir)
-      );
-    }
-
-    test.each(testCasesDirs)("Case %s", async (dirName: string) => {
-      const testCasePath = testsCasesPath + "/" + dirName;
-      const normalizedHtmls = await getNormalizedHtml(testCasePath, vendor);
-      const { sentHtml, receivedHtml } = normalizedHtmls;
-
-      // expect(receivedHtml.length).toBeGreaterThan(0);
-      // expect(sentHtml.length).toBeGreaterThan(0);
-
-      // eslint-disable-next-line
-      // @ts-ignore
-      // console.log(receivedHtml);
-      expect(receivedHtml).toEqualWithDiff(sentHtml);
-    });
-  };
-
-export const createDescribePlainTestCases = (testsPath: string) => (
-  casesName: string,
-  failingCases: Array<string> = [],
-  casesToCheckOnly?: Array<string>
-) => (): void => {
-  const testsCasesPath = testsPath + "/" + casesName;
-  let testCasesDirs = getTestCasesDirs(testsCasesPath);
-
-  if (casesToCheckOnly && casesToCheckOnly.length) {
-    testCasesDirs = testCasesDirs.filter((dir) =>
-      casesToCheckOnly.includes(dir)
-    );
-  }
-
-  if (failingCases && failingCases.length) {
-    testCasesDirs = testCasesDirs.filter((dir) => !failingCases.includes(dir));
-  }
-
-  test.each(testCasesDirs)("Case %s", async (dirName: string) => {
-    const testCasePath = testsCasesPath + "/" + dirName;
-    const normalizedPlain = await getNormalizedPlain(testCasePath);
-
-    const { sentPlain, receivedPlain } = normalizedPlain;
-    // expect(sentPlain.length).toBeGreaterThan(0);
-    // expect(receivedPlain.length).toBeGreaterThan(0);
-    // eslint-disable-next-line
-    // @ts-ignore
-    expect(receivedPlain).toEqualWithDiff(sentPlain);
-  });
-};
-
-export const createDescribePseudoPlainTestCases = (
-  testsPath: string,
-  vendor: string
-) =>
-  /**
-   * @param casesGroupName - name of the folder with cases
-   * @param failingCases - a list of cases that are failing and ignored. Pending to be fixed
-   * @param casesToCheckOnly - a filter to use if you want to check specific cases
-   */
-  (
-    casesGroupName: string,
-    failingCases?: Array<string>,
-    casesToCheckOnly?: Array<string>
-  ) => (): void => {
-    const testsCasesPath = testsPath + "/" + casesGroupName;
-    let testCasesDirs = getTestCasesDirs(testsCasesPath);
-
-    if (casesToCheckOnly && casesToCheckOnly.length) {
-      testCasesDirs = testCasesDirs.filter((dir) =>
-        casesToCheckOnly.includes(dir)
-      );
-    }
-
-    if (failingCases && failingCases.length) {
-      testCasesDirs = testCasesDirs.filter(
-        (dir) => !failingCases.includes(dir)
-      );
-    }
-
-    test.each(testCasesDirs)("Case %s", async (dirName: string) => {
-      const testCasePath = testsCasesPath + "/" + dirName;
-      const { sentHtmlDocument, receivedHtmlDocument } = await getDOMDocuments(
-        testCasePath
-      );
-
-      HTMLNormalizer.normalizeVendorHtml(sentHtmlDocument, vendor);
-      HTMLNormalizer.normalizeVendorHtml(receivedHtmlDocument, vendor);
-
-      const normalizedSentPseudoPlainText = HTMLNormalizer.extractPseudoPlainPart(
-        sentHtmlDocument
-      );
-
-      const normalizedReceivedPseudoPlainText = HTMLNormalizer.extractPseudoPlainPart(
-        receivedHtmlDocument
-      );
-
-      // eslint-disable-next-line
-      // @ts-ignore
-      expect(normalizedReceivedPseudoPlainText).toEqualWithDiff(
-        normalizedSentPseudoPlainText
-      );
-    });
-  };
-
-export const getDOMDocuments = async (
-  testCasePath: string
-): Promise<{
-  sentHtmlDocument: HTMLDocument;
-  receivedHtmlDocument: HTMLDocument;
-}> => {
-  const sentMime = getMime(`${testCasePath}/${SENT_EML_NAME}`);
-  const receivedMime = getMime(`${testCasePath}/${RECEIVED_EML_NAME}`);
-
-  const sentDOM = new DOM(
-    await sentMime.getHTML({ populateAttachments, hashAttachment })
-  );
-  const receivedDOM = new JSDOM(
-    await receivedMime.getHTML({ populateAttachments, hashAttachment })
-  );
-
-  return {
-    sentHtmlDocument: sentDOM.window.document,
-    receivedHtmlDocument: receivedDOM.window.document,
-  };
-};
diff --git a/jest.config.js b/jest.config.js
index 216e02ed6b0bfb29264c3d559ea89249c600c2df..66ae80cdd4bba7aaec809bee515613485768a34c 100644
--- a/jest.config.js
+++ b/jest.config.js
@@ -82,7 +82,7 @@ module.exports = {
   // moduleNameMapper: {},
 
   // An array of regexp pattern strings, matched against all module paths before considered 'visible' to the module loader
-  modulePathIgnorePatterns: ["__tests__/utils.ts"],
+  // modulePathIgnorePatterns: ["__tests__/utils.ts"],
 
   // Activates notifications for test results
   // notify: false,
@@ -144,10 +144,10 @@ module.exports = {
   // testLocationInResults: false,
 
   // The glob patterns Jest uses to detect test files
-  // testMatch: [
-  //   "**/__tests__/**/*.[jt]s?(x)",
-  //   "**/?(*.)+(spec|test).[tj]s?(x)"
-  // ],
+  testMatch: [
+    // "**/__tests__/**/*.[jt]s?(x)",
+    "**/?(*.)+(spec|test).[tj]s?(x)",
+  ],
 
   // An array of regexp pattern strings that are matched against all test paths, matched tests are skipped
   testPathIgnorePatterns: ["/node_modules/", "setupFiles.js"],