diff --git a/externals/tXml.js b/externals/tXml.js
index 3a706c2233..db6c43296a 100644
--- a/externals/tXml.js
+++ b/externals/tXml.js
@@ -52,11 +52,11 @@ export const XML_ENTITIES = {
 
 /**
  * Translates XML predefined entities and character references to their respective characters.
- * @param {Object} entitiesList 
- * @param {String} str 
+ * @param {Object} entitiesList
+ * @param {String} str
  * @returns {String}
  */
-function translateEntitiesAndCharacterReferences(entitiesList, str) {
+export function translateEntitiesAndCharacterReferences(entitiesList, str) {
     const entitySplit = str.split(/(&[#a-zA-Z0-9]+;)/);
     if (entitySplit.length <= 1) { // No entities. Skip the rest of the function.
         return str;
@@ -64,7 +64,7 @@ function translateEntitiesAndCharacterReferences(entitiesList, str) {
 
     for (let i = 1; i < entitySplit.length; i += 2) {
         const reference = entitySplit[i];
-        
+
         /*
          * Check if it is a character reference of the form
          * /&#[0-9]+;/ - Encoded in decimal, or
@@ -83,7 +83,7 @@ function translateEntitiesAndCharacterReferences(entitiesList, str) {
             if (!isNaN(code) && code >= 0 && code <= 0x10FFFF) {
                 entitySplit[i] = String.fromCodePoint(code);
             }
-        } 
+        }
         /*
          * Translate entity references using a dictionary.
          */
diff --git a/test/unit/externals.tXml.js b/test/unit/externals.tXml.js
new file mode 100644
index 0000000000..69d99086db
--- /dev/null
+++ b/test/unit/externals.tXml.js
@@ -0,0 +1,62 @@
+import {expect} from 'chai';
+import {translateEntitiesAndCharacterReferences, XML_ENTITIES} from '../../externals/tXml.js'
+
+describe('tXml', () => {
+
+    describe('translateEntitiesAndCharacterReferences', () => {
+
+        it('should not change string without XML entities', () => {
+            expect(translateEntitiesAndCharacterReferences(XML_ENTITIES, 'PT634')).to.be.equal('PT634')
+        })
+
+        it('should translate general entity amp', () => {
+            expect(translateEntitiesAndCharacterReferences(XML_ENTITIES, 'PT634&amp;')).to.be.equal('PT634&')
+        })
+
+        it('should translate general entity lt', () => {
+            expect(translateEntitiesAndCharacterReferences(XML_ENTITIES, 'PT634&lt;')).to.be.equal('PT634<')
+        })
+
+        it('should translate general entity gt', () => {
+            expect(translateEntitiesAndCharacterReferences(XML_ENTITIES, 'PT634&gt;')).to.be.equal('PT634>')
+        })
+
+        it('should translate general entity apos', () => {
+            expect(translateEntitiesAndCharacterReferences(XML_ENTITIES, 'PT634&apos;')).to.be.equal('PT634\'')
+        })
+
+        it('should translate general entity quot', () => {
+            expect(translateEntitiesAndCharacterReferences(XML_ENTITIES, 'PT634&quot;')).to.be.equal('PT634"')
+        })
+
+        it('should translate all general entities', () => {
+            const input = '&amp; &gt; &lt; &quot; &apos;';
+            const expectedOutput = '& > < " \'';
+            expect(translateEntitiesAndCharacterReferences(XML_ENTITIES, input)).to.be.equal(expectedOutput)
+        })
+
+        it('should correctly translate decimal character references', () => {
+            const input = '&#65; &#66; &#67;';
+            const expectedOutput = 'A B C';
+            expect(translateEntitiesAndCharacterReferences(XML_ENTITIES, input)).to.be.equal(expectedOutput)
+        })
+
+        it('should correctly translate hexadecimal character references', () => {
+            const input = '&#x41; &#x42; &#x43;';
+            const expectedOutput = 'A B C';
+            expect(translateEntitiesAndCharacterReferences(XML_ENTITIES, input)).to.be.equal(expectedOutput)
+        })
+
+        it('should correctly translate character references mixed with other text', () => {
+            const input = 'This is a test: &#65; &#66; &#67;';
+            const expectedOutput = 'This is a test: A B C';
+            expect(translateEntitiesAndCharacterReferences(XML_ENTITIES, input)).to.be.equal(expectedOutput)
+        })
+
+        it('should correctly translate character references mixed with general entities and other text', () => {
+            const input = 'This is a test: &#65; &#66; &#67; &amp; &gt; &lt; &quot; &apos;';
+            const expectedOutput = 'This is a test: A B C & > < " \'';
+            expect(translateEntitiesAndCharacterReferences(XML_ENTITIES, input)).to.be.equal(expectedOutput)
+        })
+    })
+})