diff --git a/src/core/fonts.js b/src/core/fonts.js
index 0301d49ad..29f186fa3 100644
--- a/src/core/fonts.js
+++ b/src/core/fonts.js
@@ -3293,6 +3293,47 @@ class Font {
     return builder.toArray();
   }
 
+  /**
+   * @private
+   */
+  get _spaceWidth() {
+    // trying to estimate space character width
+    const possibleSpaceReplacements = ["space", "minus", "one", "i", "I"];
+    let width;
+    for (const glyphName of possibleSpaceReplacements) {
+      // if possible, getting width by glyph name
+      if (glyphName in this.widths) {
+        width = this.widths[glyphName];
+        break;
+      }
+      const glyphsUnicodeMap = getGlyphsUnicode();
+      const glyphUnicode = glyphsUnicodeMap[glyphName];
+      // finding the charcode via unicodeToCID map
+      let charcode = 0;
+      if (this.composite && this.cMap.contains(glyphUnicode)) {
+        charcode = this.cMap.lookup(glyphUnicode);
+
+        if (typeof charcode === "string") {
+          charcode = convertCidString(glyphUnicode, charcode);
+        }
+      }
+      // ... via toUnicode map
+      if (!charcode && this.toUnicode) {
+        charcode = this.toUnicode.charCodeOf(glyphUnicode);
+      }
+      // setting it to unicode if negative or undefined
+      if (charcode <= 0) {
+        charcode = glyphUnicode;
+      }
+      // trying to get width via charcode
+      width = this.widths[charcode];
+      if (width) {
+        break; // the non-zero width found
+      }
+    }
+    return shadow(this, "_spaceWidth", width || this.defaultWidth);
+  }
+
   /**
    * @private
    */
@@ -3338,6 +3379,13 @@ class Font {
         // .notdef glyphs should be invisible in non-embedded Type1 fonts, so
         // replace them with spaces.
         fontCharCode = 0x20;
+
+        if (glyphName === "") {
+          // Ensure that other relevant glyph properties are also updated
+          // (fixes issue18059.pdf).
+          width ||= this._spaceWidth;
+          unicode = String.fromCharCode(fontCharCode);
+        }
       }
       fontCharCode = mapSpecialUnicodeValues(fontCharCode);
     }
diff --git a/test/pdfs/.gitignore b/test/pdfs/.gitignore
index 8629cd5bc..df69d2255 100644
--- a/test/pdfs/.gitignore
+++ b/test/pdfs/.gitignore
@@ -57,6 +57,7 @@
 !issue17679_2.pdf
 !issue18030.pdf
 !issue18042.pdf
+!issue18059.pdf
 !issue14953.pdf
 !issue15367.pdf
 !issue15372.pdf
diff --git a/test/pdfs/issue18059.pdf b/test/pdfs/issue18059.pdf
new file mode 100644
index 000000000..82416e266
Binary files /dev/null and b/test/pdfs/issue18059.pdf differ
diff --git a/test/test_manifest.json b/test/test_manifest.json
index 78c4d8f59..90ad056ec 100644
--- a/test/test_manifest.json
+++ b/test/test_manifest.json
@@ -2983,6 +2983,27 @@
     "rounds": 1,
     "type": "eq"
   },
+  {
+    "id": "issue11403-text",
+    "file": "pdfs/issue11403_reduced.pdf",
+    "md5": "08287b64f442cb7c329b97c4774aa1cd",
+    "rounds": 1,
+    "type": "text"
+  },
+  {
+    "id": "issue18059",
+    "file": "pdfs/issue18059.pdf",
+    "md5": "b70373894edfcd571a41caa1a0776b6f",
+    "rounds": 1,
+    "type": "eq"
+  },
+  {
+    "id": "issue18059-text",
+    "file": "pdfs/issue18059.pdf",
+    "md5": "b70373894edfcd571a41caa1a0776b6f",
+    "rounds": 1,
+    "type": "text"
+  },
   {
     "id": "issue11139",
     "file": "pdfs/issue11139.pdf",
@@ -6479,6 +6500,14 @@
     "type": "eq",
     "about": "Has a 4 bit per component image with mask and decode."
   },
+  {
+    "id": "issue2770-text",
+    "file": "pdfs/issue2770.pdf",
+    "md5": "36070d756d06eaa35c2227efb069fb1b",
+    "rounds": 1,
+    "link": true,
+    "type": "text"
+  },
   {
     "id": "issue2984",
     "file": "pdfs/issue2984.pdf",