diff --git a/AUTHORS b/AUTHORS
index cdae2fc99..0e4b9b73f 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -247,5 +247,6 @@ Sukka <isukkaw@gmail.com>
 Rohil Shah <shah5963@gmail.com>
 Laurent Gérin <41303636+lgerin@users.noreply.github.com>
 Adam Jones <domdomegg+git@gmail.com>
+Lucas Eng <lucaseng19@gmail.com>
 
 # Generated by tools/update-authors.js
diff --git a/HISTORY.md b/HISTORY.md
index 6292ff2ce..a5abab9c0 100644
--- a/HISTORY.md
+++ b/HISTORY.md
@@ -1,6 +1,6 @@
 # History
 
-# unpublished changes since 12.4.2
+# 2024-05-31, 12.4.3
 
 - Fix: serialization of Units without a value, see #1240.
 - Fix: outdated, incorrect documentation about the order of precedence for
diff --git a/package.json b/package.json
index 3cf884b7a..100d95259 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "mathjs",
-  "version": "12.4.2",
+  "version": "12.4.3",
   "description": "Math.js is an extensive math library for JavaScript and Node.js. It features a flexible expression parser with support for symbolic computation, comes with a large set of built-in functions and constants, and offers an integrated solution to work with different data types like numbers, big numbers, complex numbers, fractions, units, and matrices.",
   "author": "Jos de Jong <wjosdejong@gmail.com> (https://github.com/josdejong)",
   "homepage": "https://mathjs.org",
diff --git a/src/version.js b/src/version.js
index 48f9706d1..6cf204477 100644
--- a/src/version.js
+++ b/src/version.js
@@ -1,3 +1,3 @@
-export const version = '12.4.2'
+export const version = '12.4.3'
 // Note: This file is automatically generated when building math.js.
 // Changes made in this file will be overwritten.
diff --git a/test/unit-tests/type/matrix/utils/deepForEach.test.js b/test/unit-tests/type/matrix/utils/deepForEach.test.js
index 36d0e030c..6245eb380 100644
--- a/test/unit-tests/type/matrix/utils/deepForEach.test.js
+++ b/test/unit-tests/type/matrix/utils/deepForEach.test.js
@@ -1 +1,63 @@
-// TODO: test deepForEach
+import assert from 'assert'
+import math from '../../../../../src/defaultInstance.js'
+import { deepForEach } from '../../../../../src/utils/collection.js'
+
+const DenseMatrix = math.DenseMatrix
+
+describe('deepForEach', function () {
+  it('should iterate over all elements in a simple array', function () {
+    const array = [1, 2, 3]
+    const result = []
+    deepForEach(array, value => result.push(value))
+    assert.deepStrictEqual(result, [1, 2, 3])
+  })
+
+  it('should iterate over all elements in a nested array', function () {
+    const array = [[1, 2], [3, [4, 5]]]
+    const result = []
+    deepForEach(array, value => result.push(value))
+    assert.deepStrictEqual(result, [1, 2, 3, 4, 5])
+  })
+
+  it('should iterate over all elements in a mixed type array', function () {
+    const array = [1, 'two', [3, null, undefined, true]]
+    const result = []
+    deepForEach(array, value => result.push(value))
+    assert.deepStrictEqual(result, [1, 'two', 3, null, undefined, true])
+  })
+
+  it('should handle an empty array', function () {
+    const array = []
+    const result = []
+    deepForEach(array, value => result.push(value))
+    assert.deepStrictEqual(result, [])
+  })
+
+  it('should handle an array with empty nested arrays', function () {
+    const array = [[], [1, []], [2, [3, []]]]
+    const result = []
+    deepForEach(array, value => result.push(value))
+    assert.deepStrictEqual(result, [1, 2, 3])
+  })
+
+  it('should iterate over all elements in a DenseMatrix', function () {
+    const matrix = new DenseMatrix([[1, 2], [3, 4]])
+    const result = []
+    deepForEach(matrix, value => result.push(value))
+    assert.deepStrictEqual(result, [1, 2, 3, 4])
+  })
+
+  it('should call the callback with each element of a matrix after converting to array', function () {
+    const matrix = math.matrix([[1, 2], [3, 4]])
+    const result = []
+    deepForEach(matrix, value => result.push(value))
+    assert.deepStrictEqual(result, [1, 2, 3, 4])
+  })
+
+  it('should work with arrays containing complex numbers', function () {
+    const array = [math.complex(2, 3), [math.complex(4, 5)]]
+    const result = []
+    deepForEach(array, value => result.push(value))
+    assert.deepStrictEqual(result, [math.complex(2, 3), math.complex(4, 5)])
+  })
+})