diff --git a/src/core/core_utils.js b/src/core/core_utils.js
index a4c23b7c2..af1d01246 100644
--- a/src/core/core_utils.js
+++ b/src/core/core_utils.js
@@ -17,9 +17,7 @@ import {
   AnnotationEditorPrefix,
   assert,
   BaseException,
-  FontType,
   objectSize,
-  StreamType,
   stringToPDFString,
   warn,
 } from "../shared/util.js";
@@ -82,55 +80,6 @@ class XRefParseException extends BaseException {
   }
 }
 
-class DocStats {
-  constructor(handler) {
-    this._handler = handler;
-
-    this._streamTypes = new Set();
-    this._fontTypes = new Set();
-  }
-
-  _send() {
-    const streamTypes = Object.create(null),
-      fontTypes = Object.create(null);
-    for (const type of this._streamTypes) {
-      streamTypes[type] = true;
-    }
-    for (const type of this._fontTypes) {
-      fontTypes[type] = true;
-    }
-    this._handler.send("DocStats", { streamTypes, fontTypes });
-  }
-
-  addStreamType(type) {
-    if (
-      typeof PDFJSDev === "undefined" ||
-      PDFJSDev.test("!PRODUCTION || TESTING")
-    ) {
-      assert(StreamType[type] === type, 'addStreamType: Invalid "type" value.');
-    }
-    if (this._streamTypes.has(type)) {
-      return;
-    }
-    this._streamTypes.add(type);
-    this._send();
-  }
-
-  addFontType(type) {
-    if (
-      typeof PDFJSDev === "undefined" ||
-      PDFJSDev.test("!PRODUCTION || TESTING")
-    ) {
-      assert(FontType[type] === type, 'addFontType: Invalid "type" value.');
-    }
-    if (this._fontTypes.has(type)) {
-      return;
-    }
-    this._fontTypes.add(type);
-    this._send();
-  }
-}
-
 /**
  * Get the value of an inheritable property.
  *
@@ -631,7 +580,6 @@ function getRotationMatrix(rotation, width, height) {
 
 export {
   collectActions,
-  DocStats,
   encodeToXmlString,
   escapePDFName,
   escapeString,
diff --git a/src/core/document.js b/src/core/document.js
index e733d881c..a3214f3e6 100644
--- a/src/core/document.js
+++ b/src/core/document.js
@@ -222,11 +222,13 @@ class Page {
    */
   _onSubStreamError(handler, reason, objId) {
     if (this.evaluatorOptions.ignoreErrors) {
-      // Error(s) when reading one of the /Contents sub-streams -- sending
-      // unsupported feature notification and allow parsing to continue.
-      handler.send("UnsupportedFeature", {
-        featureId: UNSUPPORTED_FEATURES.errorContentSubStream,
-      });
+      if (typeof PDFJSDev === "undefined" || PDFJSDev.test("GENERIC")) {
+        // Error(s) when reading one of the /Contents sub-streams -- sending
+        // unsupported feature notification and allow parsing to continue.
+        handler.send("UnsupportedFeature", {
+          featureId: UNSUPPORTED_FEATURES.errorContentSubStream,
+        });
+      }
       warn(`getContentStream - ignoring sub-stream (${objId}): "${reason}".`);
       return;
     }
diff --git a/src/core/evaluator.js b/src/core/evaluator.js
index 4b540ac07..0054576ff 100644
--- a/src/core/evaluator.js
+++ b/src/core/evaluator.js
@@ -35,7 +35,6 @@ import {
 import { CMapFactory, IdentityCMap } from "./cmap.js";
 import { Cmd, Dict, EOF, isName, Name, Ref, RefSet } from "./primitives.js";
 import { ErrorFont, Font } from "./fonts.js";
-import { FontFlags, getFontType } from "./fonts_utils.js";
 import {
   getEncoding,
   MacRomanEncoding,
@@ -67,6 +66,7 @@ import { BaseStream } from "./base_stream.js";
 import { bidi } from "./bidi.js";
 import { ColorSpace } from "./colorspace.js";
 import { DecodeStream } from "./decode_stream.js";
+import { FontFlags } from "./fonts_utils.js";
 import { getGlyphsUnicode } from "./glyphlist.js";
 import { getLookupTableFactory } from "./core_utils.js";
 import { getMetrics } from "./metrics.js";
@@ -929,11 +929,13 @@ class PartialEvaluator {
           return;
         }
         if (this.options.ignoreErrors) {
-          // Error(s) in the TilingPattern -- sending unsupported feature
-          // notification and allow rendering to continue.
-          this.handler.send("UnsupportedFeature", {
-            featureId: UNSUPPORTED_FEATURES.errorTilingPattern,
-          });
+          if (typeof PDFJSDev === "undefined" || PDFJSDev.test("GENERIC")) {
+            // Error(s) in the TilingPattern -- sending unsupported feature
+            // notification and allow rendering to continue.
+            this.handler.send("UnsupportedFeature", {
+              featureId: UNSUPPORTED_FEATURES.errorTilingPattern,
+            });
+          }
           warn(`handleTilingType - ignoring pattern: "${reason}".`);
           return;
         }
@@ -975,11 +977,13 @@ class PartialEvaluator {
             return translated;
           })
           .catch(reason => {
-            // Error in the font data -- sending unsupported feature
-            // notification.
-            this.handler.send("UnsupportedFeature", {
-              featureId: UNSUPPORTED_FEATURES.errorFontLoadType3,
-            });
+            if (typeof PDFJSDev === "undefined" || PDFJSDev.test("GENERIC")) {
+              // Error in the font data -- sending unsupported feature
+              // notification.
+              this.handler.send("UnsupportedFeature", {
+                featureId: UNSUPPORTED_FEATURES.errorFontLoadType3,
+              });
+            }
             return new TranslatedFont({
               loadedName: "g_font_error",
               font: new ErrorFont(`Type3 font load error: ${reason}`),
@@ -1029,11 +1033,13 @@ class PartialEvaluator {
     );
 
     if (this.options.ignoreErrors) {
-      // Missing setFont operator before text rendering operator -- sending
-      // unsupported feature notification and allow rendering to continue.
-      this.handler.send("UnsupportedFeature", {
-        featureId: UNSUPPORTED_FEATURES.errorFontState,
-      });
+      if (typeof PDFJSDev === "undefined" || PDFJSDev.test("GENERIC")) {
+        // Missing setFont operator before text rendering operator -- sending
+        // unsupported feature notification and allow rendering to continue.
+        this.handler.send("UnsupportedFeature", {
+          featureId: UNSUPPORTED_FEATURES.errorFontState,
+        });
+      }
       warn(`ensureStateFont: "${reason}".`);
       return;
     }
@@ -1191,10 +1197,12 @@ class PartialEvaluator {
         warn(`${partialMsg}.`);
         return errorFont();
       }
-      // Font not found -- sending unsupported feature notification.
-      this.handler.send("UnsupportedFeature", {
-        featureId: UNSUPPORTED_FEATURES.errorFontMissing,
-      });
+      if (typeof PDFJSDev === "undefined" || PDFJSDev.test("GENERIC")) {
+        // Font not found -- sending unsupported feature notification.
+        this.handler.send("UnsupportedFeature", {
+          featureId: UNSUPPORTED_FEATURES.errorFontMissing,
+        });
+      }
       warn(`${partialMsg} -- attempting to fallback to a default font.`);
 
       // Falling back to a default font to avoid completely broken rendering,
@@ -1302,10 +1310,6 @@ class PartialEvaluator {
 
     this.translateFont(preEvaluatedFont)
       .then(translatedFont => {
-        if (translatedFont.fontType !== undefined) {
-          xref.stats.addFontType(translatedFont.fontType);
-        }
-
         fontCapability.resolve(
           new TranslatedFont({
             loadedName: font.loadedName,
@@ -1317,25 +1321,14 @@ class PartialEvaluator {
       })
       .catch(reason => {
         // TODO fontCapability.reject?
-        // Error in the font data -- sending unsupported feature notification.
-        this.handler.send("UnsupportedFeature", {
-          featureId: UNSUPPORTED_FEATURES.errorFontTranslate,
-        });
+        if (typeof PDFJSDev === "undefined" || PDFJSDev.test("GENERIC")) {
+          // Error in the font data -- sending unsupported feature notification.
+          this.handler.send("UnsupportedFeature", {
+            featureId: UNSUPPORTED_FEATURES.errorFontTranslate,
+          });
+        }
         warn(`loadFont - translateFont failed: "${reason}".`);
 
-        try {
-          // error, but it's still nice to have font type reported
-          const fontFile3 = descriptor && descriptor.get("FontFile3");
-          const subtype = fontFile3 && fontFile3.get("Subtype");
-          const fontType = getFontType(
-            preEvaluatedFont.type,
-            subtype && subtype.name
-          );
-          if (fontType !== undefined) {
-            xref.stats.addFontType(fontType);
-          }
-        } catch (ex) {}
-
         fontCapability.resolve(
           new TranslatedFont({
             loadedName: font.loadedName,
@@ -1439,11 +1432,13 @@ class PartialEvaluator {
         return null;
       }
       if (this.options.ignoreErrors) {
-        // Error(s) in the ColorSpace -- sending unsupported feature
-        // notification and allow rendering to continue.
-        this.handler.send("UnsupportedFeature", {
-          featureId: UNSUPPORTED_FEATURES.errorColorSpace,
-        });
+        if (typeof PDFJSDev === "undefined" || PDFJSDev.test("GENERIC")) {
+          // Error(s) in the ColorSpace -- sending unsupported feature
+          // notification and allow rendering to continue.
+          this.handler.send("UnsupportedFeature", {
+            featureId: UNSUPPORTED_FEATURES.errorColorSpace,
+          });
+        }
         warn(`parseColorSpace - ignoring ColorSpace: "${reason}".`);
         return null;
       }
@@ -1828,11 +1823,16 @@ class PartialEvaluator {
                   return;
                 }
                 if (self.options.ignoreErrors) {
-                  // Error(s) in the XObject -- sending unsupported feature
-                  // notification and allow rendering to continue.
-                  self.handler.send("UnsupportedFeature", {
-                    featureId: UNSUPPORTED_FEATURES.errorXObject,
-                  });
+                  if (
+                    typeof PDFJSDev === "undefined" ||
+                    PDFJSDev.test("GENERIC")
+                  ) {
+                    // Error(s) in the XObject -- sending unsupported feature
+                    // notification and allow rendering to continue.
+                    self.handler.send("UnsupportedFeature", {
+                      featureId: UNSUPPORTED_FEATURES.errorXObject,
+                    });
+                  }
                   warn(`getOperatorList - ignoring XObject: "${reason}".`);
                   return;
                 }
@@ -2147,11 +2147,16 @@ class PartialEvaluator {
                   return;
                 }
                 if (self.options.ignoreErrors) {
-                  // Error(s) in the ExtGState -- sending unsupported feature
-                  // notification and allow parsing/rendering to continue.
-                  self.handler.send("UnsupportedFeature", {
-                    featureId: UNSUPPORTED_FEATURES.errorExtGState,
-                  });
+                  if (
+                    typeof PDFJSDev === "undefined" ||
+                    PDFJSDev.test("GENERIC")
+                  ) {
+                    // Error(s) in the ExtGState -- sending unsupported feature
+                    // notification and allow parsing/rendering to continue.
+                    self.handler.send("UnsupportedFeature", {
+                      featureId: UNSUPPORTED_FEATURES.errorExtGState,
+                    });
+                  }
                   warn(`getOperatorList - ignoring ExtGState: "${reason}".`);
                   return;
                 }
@@ -2199,9 +2204,14 @@ class PartialEvaluator {
                       return;
                     }
                     if (self.options.ignoreErrors) {
-                      self.handler.send("UnsupportedFeature", {
-                        featureId: UNSUPPORTED_FEATURES.errorMarkedContent,
-                      });
+                      if (
+                        typeof PDFJSDev === "undefined" ||
+                        PDFJSDev.test("GENERIC")
+                      ) {
+                        self.handler.send("UnsupportedFeature", {
+                          featureId: UNSUPPORTED_FEATURES.errorMarkedContent,
+                        });
+                      }
                       warn(
                         `getOperatorList - ignoring beginMarkedContentProps: "${reason}".`
                       );
@@ -2252,11 +2262,13 @@ class PartialEvaluator {
         return;
       }
       if (this.options.ignoreErrors) {
-        // Error(s) in the OperatorList -- sending unsupported feature
-        // notification and allow rendering to continue.
-        this.handler.send("UnsupportedFeature", {
-          featureId: UNSUPPORTED_FEATURES.errorOperatorList,
-        });
+        if (typeof PDFJSDev === "undefined" || PDFJSDev.test("GENERIC")) {
+          // Error(s) in the OperatorList -- sending unsupported feature
+          // notification and allow rendering to continue.
+          this.handler.send("UnsupportedFeature", {
+            featureId: UNSUPPORTED_FEATURES.errorOperatorList,
+          });
+        }
         warn(
           `getOperatorList - ignoring errors during "${task.name}" ` +
             `task: "${reason}".`
@@ -3751,11 +3763,13 @@ class PartialEvaluator {
             return null;
           }
           if (this.options.ignoreErrors) {
-            // Error in the ToUnicode data -- sending unsupported feature
-            // notification and allow font parsing to continue.
-            this.handler.send("UnsupportedFeature", {
-              featureId: UNSUPPORTED_FEATURES.errorFontToUnicode,
-            });
+            if (typeof PDFJSDev === "undefined" || PDFJSDev.test("GENERIC")) {
+              // Error in the ToUnicode data -- sending unsupported feature
+              // notification and allow font parsing to continue.
+              this.handler.send("UnsupportedFeature", {
+                featureId: UNSUPPORTED_FEATURES.errorFontToUnicode,
+              });
+            }
             warn(`readToUnicode - ignoring ToUnicode data: "${reason}".`);
             return null;
           }
@@ -4329,11 +4343,13 @@ class PartialEvaluator {
         ]);
       } catch (reason) {
         if (evaluatorOptions.ignoreErrors) {
-          // Error in the font data -- sending unsupported feature notification
-          // and allow glyph path building to continue.
-          handler.send("UnsupportedFeature", {
-            featureId: UNSUPPORTED_FEATURES.errorFontBuildPath,
-          });
+          if (typeof PDFJSDev === "undefined" || PDFJSDev.test("GENERIC")) {
+            // Error in the font data -- sending unsupported feature
+            // notification and allow glyph path building to continue.
+            handler.send("UnsupportedFeature", {
+              featureId: UNSUPPORTED_FEATURES.errorFontBuildPath,
+            });
+          }
           warn(`buildFontPaths - ignoring ${glyphName} glyph: "${reason}".`);
           return;
         }
diff --git a/src/core/fonts.js b/src/core/fonts.js
index 8d02b5d0f..4d09e7234 100644
--- a/src/core/fonts.js
+++ b/src/core/fonts.js
@@ -17,7 +17,6 @@ import {
   assert,
   bytesToString,
   FONT_IDENTITY_MATRIX,
-  FontType,
   FormatError,
   info,
   shadow,
@@ -27,7 +26,6 @@ import {
 import { CFFCompiler, CFFParser } from "./cff_parser.js";
 import {
   FontFlags,
-  getFontType,
   MacStandardGlyphOrdering,
   normalizeFontName,
   recoverGlyphName,
@@ -92,7 +90,6 @@ const EXPORT_DATA_PROPERTIES = [
   "descent",
   "fallbackName",
   "fontMatrix",
-  "fontType",
   "isInvalidPDFjsFont",
   "isType3Font",
   "italic",
@@ -986,7 +983,6 @@ class Font {
         this.toFontChar[charCode] =
           this.differences[charCode] || properties.defaultEncoding[charCode];
       }
-      this.fontType = FontType.TYPE3;
       return;
     }
 
@@ -1066,7 +1062,6 @@ class Font {
 
     amendFallbackToUnicode(properties);
     this.data = data;
-    this.fontType = getFontType(type, subtype, properties.isStandardFont);
 
     // Transfer some properties again that could change during font conversion
     this.fontMatrix = properties.fontMatrix;
@@ -1102,9 +1097,7 @@ class Font {
     this.missingFile = true;
     // The file data is not specified. Trying to fix the font name
     // to be used with the canvas.font.
-    const name = this.name;
-    const type = this.type;
-    const subtype = this.subtype;
+    const { name, type } = this;
     let fontName = normalizeFontName(name);
     const stdFontMap = getStdFontMap(),
       nonStdFontMap = getNonStdFontMap();
@@ -1252,7 +1245,6 @@ class Font {
 
     amendFallbackToUnicode(properties);
     this.loadedName = fontName.split("-")[0];
-    this.fontType = getFontType(type, subtype, properties.isStandardFont);
   }
 
   checkAndRepair(name, font, properties) {
diff --git a/src/core/fonts_utils.js b/src/core/fonts_utils.js
index b67dfe01d..6287786f3 100644
--- a/src/core/fonts_utils.js
+++ b/src/core/fonts_utils.js
@@ -13,10 +13,10 @@
  * limitations under the License.
  */
 
-import { FontType, info } from "../shared/util.js";
 import { getEncoding, StandardEncoding } from "./encodings.js";
 import { getGlyphsUnicode } from "./glyphlist.js";
 import { getUnicodeForGlyph } from "./unicode.js";
+import { info } from "../shared/util.js";
 
 // Accented characters have issues on Windows and Linux. When this flag is
 // enabled glyphs that use seac and seac style endchar operators are truncated
@@ -78,32 +78,6 @@ const MacStandardGlyphOrdering = [
   "threequarters", "franc", "Gbreve", "gbreve", "Idotaccent", "Scedilla",
   "scedilla", "Cacute", "cacute", "Ccaron", "ccaron", "dcroat"];
 
-function getFontType(type, subtype, isStandardFont = false) {
-  switch (type) {
-    case "Type1":
-      if (isStandardFont) {
-        return FontType.TYPE1STANDARD;
-      }
-      return subtype === "Type1C" ? FontType.TYPE1C : FontType.TYPE1;
-    case "CIDFontType0":
-      return subtype === "CIDFontType0C"
-        ? FontType.CIDFONTTYPE0C
-        : FontType.CIDFONTTYPE0;
-    case "OpenType":
-      return FontType.OPENTYPE;
-    case "TrueType":
-      return FontType.TRUETYPE;
-    case "CIDFontType2":
-      return FontType.CIDFONTTYPE2;
-    case "MMType1":
-      return FontType.MMTYPE1;
-    case "Type0":
-      return FontType.TYPE0;
-    default:
-      return FontType.UNKNOWN;
-  }
-}
-
 // Some bad PDF generators, e.g. Scribus PDF, include glyph names
 // in a 'uniXXXX' format -- attempting to recover proper ones.
 function recoverGlyphName(name, glyphsUnicodeMap) {
@@ -212,7 +186,6 @@ function normalizeFontName(name) {
 
 export {
   FontFlags,
-  getFontType,
   MacStandardGlyphOrdering,
   normalizeFontName,
   recoverGlyphName,
diff --git a/src/core/parser.js b/src/core/parser.js
index 118c42633..0b046adfc 100644
--- a/src/core/parser.js
+++ b/src/core/parser.js
@@ -18,7 +18,6 @@ import {
   bytesToString,
   FormatError,
   info,
-  StreamType,
   warn,
 } from "../shared/util.js";
 import { Cmd, Dict, EOF, isCmd, Name, Ref } from "./primitives.js";
@@ -732,13 +731,11 @@ class Parser {
       warn(`Empty "${name}" stream.`);
       return new NullStream();
     }
-    const xrefStats = this.xref.stats;
 
     try {
       switch (name) {
         case "Fl":
         case "FlateDecode":
-          xrefStats.addStreamType(StreamType.FLATE);
           if (params) {
             return new PredictorStream(
               new FlateStream(stream, maybeLength),
@@ -749,7 +746,6 @@ class Parser {
           return new FlateStream(stream, maybeLength);
         case "LZW":
         case "LZWDecode":
-          xrefStats.addStreamType(StreamType.LZW);
           let earlyChange = 1;
           if (params) {
             if (params.has("EarlyChange")) {
@@ -764,30 +760,23 @@ class Parser {
           return new LZWStream(stream, maybeLength, earlyChange);
         case "DCT":
         case "DCTDecode":
-          xrefStats.addStreamType(StreamType.DCT);
           return new JpegStream(stream, maybeLength, params);
         case "JPX":
         case "JPXDecode":
-          xrefStats.addStreamType(StreamType.JPX);
           return new JpxStream(stream, maybeLength, params);
         case "A85":
         case "ASCII85Decode":
-          xrefStats.addStreamType(StreamType.A85);
           return new Ascii85Stream(stream, maybeLength);
         case "AHx":
         case "ASCIIHexDecode":
-          xrefStats.addStreamType(StreamType.AHX);
           return new AsciiHexStream(stream, maybeLength);
         case "CCF":
         case "CCITTFaxDecode":
-          xrefStats.addStreamType(StreamType.CCF);
           return new CCITTFaxStream(stream, maybeLength, params);
         case "RL":
         case "RunLengthDecode":
-          xrefStats.addStreamType(StreamType.RLX);
           return new RunLengthStream(stream, maybeLength);
         case "JBIG2Decode":
-          xrefStats.addStreamType(StreamType.JBIG);
           return new Jbig2Stream(stream, maybeLength, params);
       }
       warn(`Filter "${name}" is not supported.`);
diff --git a/src/core/pattern.js b/src/core/pattern.js
index 050e4e6a4..87705a305 100644
--- a/src/core/pattern.js
+++ b/src/core/pattern.js
@@ -82,9 +82,11 @@ class Pattern {
       if (ex instanceof MissingDataException) {
         throw ex;
       }
-      handler.send("UnsupportedFeature", {
-        featureId: UNSUPPORTED_FEATURES.shadingPattern,
-      });
+      if (typeof PDFJSDev === "undefined" || PDFJSDev.test("GENERIC")) {
+        handler.send("UnsupportedFeature", {
+          featureId: UNSUPPORTED_FEATURES.shadingPattern,
+        });
+      }
       warn(ex);
       return new DummyShading();
     }
diff --git a/src/core/xref.js b/src/core/xref.js
index a15cf4d09..c55715463 100644
--- a/src/core/xref.js
+++ b/src/core/xref.js
@@ -22,14 +22,13 @@ import {
   warn,
 } from "../shared/util.js";
 import { CIRCULAR_REF, Cmd, Dict, isCmd, Ref, RefSet } from "./primitives.js";
+import { Lexer, Parser } from "./parser.js";
 import {
-  DocStats,
   MissingDataException,
   ParserEOFException,
   XRefEntryException,
   XRefParseException,
 } from "./core_utils.js";
-import { Lexer, Parser } from "./parser.js";
 import { BaseStream } from "./base_stream.js";
 import { CipherTransformFactory } from "./crypto.js";
 
@@ -41,7 +40,6 @@ class XRef {
     this.xrefstms = Object.create(null);
     this._cacheMap = new Map(); // Prepare the XRef cache.
     this._pendingRefs = new RefSet();
-    this.stats = new DocStats(pdfManager.msgHandler);
     this._newPersistentRefNum = null;
     this._newTemporaryRefNum = null;
   }
diff --git a/src/display/api.js b/src/display/api.js
index 2dca8fb07..bd01cd122 100644
--- a/src/display/api.js
+++ b/src/display/api.js
@@ -609,10 +609,12 @@ class PDFDocumentLoadingTask {
    * @type {function}
    */
   set onUnsupportedFeature(callback) {
-    deprecated(
-      "The PDFDocumentLoadingTask onUnsupportedFeature property will be removed in the future."
-    );
-    this.#onUnsupportedFeature = callback;
+    if (typeof PDFJSDev === "undefined" || PDFJSDev.test("GENERIC")) {
+      deprecated(
+        "The PDFDocumentLoadingTask onUnsupportedFeature property will be removed in the future."
+      );
+      this.#onUnsupportedFeature = callback;
+    }
   }
 
   /**
@@ -758,27 +760,6 @@ class PDFDocumentProxy {
     return this._pdfInfo.fingerprints;
   }
 
-  /**
-   * @typedef {Object} PDFDocumentStats
-   * @property {Object<string, boolean>} streamTypes - Used stream types in the
-   *   document (an item is set to true if specific stream ID was used in the
-   *   document).
-   * @property {Object<string, boolean>} fontTypes - Used font types in the
-   *   document (an item is set to true if specific font ID was used in the
-   *   document).
-   */
-
-  /**
-   * @type {PDFDocumentStats | null} The current statistics about document
-   *   structures, or `null` when no statistics exists.
-   */
-  get stats() {
-    deprecated(
-      "The PDFDocumentProxy stats property will be removed in the future."
-    );
-    return this._transport.stats;
-  }
-
   /**
    * @type {boolean} True if only XFA form.
    */
@@ -2296,8 +2277,6 @@ class PDFWorker {
  * @ignore
  */
 class WorkerTransport {
-  #docStats = null;
-
   #pageCache = new Map();
 
   #pagePromises = new Map();
@@ -2341,10 +2320,6 @@ class WorkerTransport {
     return shadow(this, "annotationStorage", new AnnotationStorage());
   }
 
-  get stats() {
-    return this.#docStats;
-  }
-
   getRenderingIntent(
     intent,
     annotationMode = AnnotationMode.ENABLE,
@@ -2775,22 +2750,12 @@ class WorkerTransport {
       });
     });
 
-    messageHandler.on("DocStats", data => {
-      if (this.destroyed) {
-        return; // Ignore any pending requests if the worker was terminated.
-      }
-      // Ensure that a `PDFDocumentProxy.stats` call-site cannot accidentally
-      // modify this internal data.
-      this.#docStats = Object.freeze({
-        streamTypes: Object.freeze(data.streamTypes),
-        fontTypes: Object.freeze(data.fontTypes),
-      });
-    });
-
-    messageHandler.on(
-      "UnsupportedFeature",
-      this._onUnsupportedFeature.bind(this)
-    );
+    if (typeof PDFJSDev === "undefined" || PDFJSDev.test("GENERIC")) {
+      messageHandler.on(
+        "UnsupportedFeature",
+        this._onUnsupportedFeature.bind(this)
+      );
+    }
 
     messageHandler.on("FetchBuiltInCMap", data => {
       if (this.destroyed) {
@@ -2822,10 +2787,12 @@ class WorkerTransport {
   }
 
   _onUnsupportedFeature({ featureId }) {
-    if (this.destroyed) {
-      return; // Ignore any pending requests if the worker was terminated.
+    if (typeof PDFJSDev === "undefined" || PDFJSDev.test("GENERIC")) {
+      if (this.destroyed) {
+        return; // Ignore any pending requests if the worker was terminated.
+      }
+      this.loadingTask.onUnsupportedFeature?.(featureId);
     }
-    this.loadingTask.onUnsupportedFeature?.(featureId);
   }
 
   getData() {
diff --git a/src/display/font_loader.js b/src/display/font_loader.js
index 244ce9ca9..49a3c453d 100644
--- a/src/display/font_loader.js
+++ b/src/display/font_loader.js
@@ -30,7 +30,9 @@ class FontLoader {
     ownerDocument = globalThis.document,
     styleElement = null, // For testing only.
   }) {
-    this._onUnsupportedFeature = onUnsupportedFeature;
+    if (typeof PDFJSDev === "undefined" || PDFJSDev.test("GENERIC")) {
+      this._onUnsupportedFeature = onUnsupportedFeature;
+    }
     this._document = ownerDocument;
 
     this.nativeFontFaces = [];
@@ -88,9 +90,11 @@ class FontLoader {
         try {
           await nativeFontFace.loaded;
         } catch (ex) {
-          this._onUnsupportedFeature({
-            featureId: UNSUPPORTED_FEATURES.errorFontLoadNative,
-          });
+          if (typeof PDFJSDev === "undefined" || PDFJSDev.test("GENERIC")) {
+            this._onUnsupportedFeature({
+              featureId: UNSUPPORTED_FEATURES.errorFontLoadNative,
+            });
+          }
           warn(`Failed to load font '${nativeFontFace.family}': '${ex}'.`);
 
           // When font loading failed, fall back to the built-in font renderer.
@@ -340,7 +344,9 @@ class FontFaceObject {
     this.isEvalSupported = isEvalSupported !== false;
     this.disableFontFace = disableFontFace === true;
     this.ignoreErrors = ignoreErrors === true;
-    this._onUnsupportedFeature = onUnsupportedFeature;
+    if (typeof PDFJSDev === "undefined" || PDFJSDev.test("GENERIC")) {
+      this._onUnsupportedFeature = onUnsupportedFeature;
+    }
     this.fontRegistry = fontRegistry;
   }
 
@@ -403,9 +409,11 @@ class FontFaceObject {
       if (!this.ignoreErrors) {
         throw ex;
       }
-      this._onUnsupportedFeature({
-        featureId: UNSUPPORTED_FEATURES.errorFontGetPath,
-      });
+      if (typeof PDFJSDev === "undefined" || PDFJSDev.test("GENERIC")) {
+        this._onUnsupportedFeature({
+          featureId: UNSUPPORTED_FEATURES.errorFontGetPath,
+        });
+      }
       warn(`getPathGenerator - ignoring character: "${ex}".`);
 
       return (this.compiledGlyphs[character] = function (c, size) {
diff --git a/src/shared/util.js b/src/shared/util.js
index c45ce201f..c3d49636f 100644
--- a/src/shared/util.js
+++ b/src/shared/util.js
@@ -236,34 +236,6 @@ const PageActionEventType = {
   C: "PageClose",
 };
 
-const StreamType = {
-  UNKNOWN: "UNKNOWN",
-  FLATE: "FLATE",
-  LZW: "LZW",
-  DCT: "DCT",
-  JPX: "JPX",
-  JBIG: "JBIG",
-  A85: "A85",
-  AHX: "AHX",
-  CCF: "CCF",
-  RLX: "RLX", // PDF short name is 'RL', but telemetry requires three chars.
-};
-
-const FontType = {
-  UNKNOWN: "UNKNOWN",
-  TYPE1: "TYPE1",
-  TYPE1STANDARD: "TYPE1STANDARD",
-  TYPE1C: "TYPE1C",
-  CIDFONTTYPE0: "CIDFONTTYPE0",
-  CIDFONTTYPE0C: "CIDFONTTYPE0C",
-  TRUETYPE: "TRUETYPE",
-  CIDFONTTYPE2: "CIDFONTTYPE2",
-  TYPE3: "TYPE3",
-  OPENTYPE: "OPENTYPE",
-  TYPE0: "TYPE0",
-  MMTYPE1: "MMTYPE1",
-};
-
 const VerbosityLevel = {
   ERRORS: 0,
   WARNINGS: 1,
@@ -374,28 +346,31 @@ const OPS = {
   constructPath: 91,
 };
 
-const UNSUPPORTED_FEATURES = {
-  forms: "forms",
-  javaScript: "javaScript",
-  signatures: "signatures",
-  smask: "smask",
-  shadingPattern: "shadingPattern",
-  errorTilingPattern: "errorTilingPattern",
-  errorExtGState: "errorExtGState",
-  errorXObject: "errorXObject",
-  errorFontLoadType3: "errorFontLoadType3",
-  errorFontState: "errorFontState",
-  errorFontMissing: "errorFontMissing",
-  errorFontTranslate: "errorFontTranslate",
-  errorColorSpace: "errorColorSpace",
-  errorOperatorList: "errorOperatorList",
-  errorFontToUnicode: "errorFontToUnicode",
-  errorFontLoadNative: "errorFontLoadNative",
-  errorFontBuildPath: "errorFontBuildPath",
-  errorFontGetPath: "errorFontGetPath",
-  errorMarkedContent: "errorMarkedContent",
-  errorContentSubStream: "errorContentSubStream",
-};
+const UNSUPPORTED_FEATURES =
+  typeof PDFJSDev === "undefined" || PDFJSDev.test("GENERIC")
+    ? {
+        forms: "forms",
+        javaScript: "javaScript",
+        signatures: "signatures",
+        smask: "smask",
+        shadingPattern: "shadingPattern",
+        errorTilingPattern: "errorTilingPattern",
+        errorExtGState: "errorExtGState",
+        errorXObject: "errorXObject",
+        errorFontLoadType3: "errorFontLoadType3",
+        errorFontState: "errorFontState",
+        errorFontMissing: "errorFontMissing",
+        errorFontTranslate: "errorFontTranslate",
+        errorColorSpace: "errorColorSpace",
+        errorOperatorList: "errorOperatorList",
+        errorFontToUnicode: "errorFontToUnicode",
+        errorFontLoadNative: "errorFontLoadNative",
+        errorFontBuildPath: "errorFontBuildPath",
+        errorFontGetPath: "errorFontGetPath",
+        errorMarkedContent: "errorMarkedContent",
+        errorContentSubStream: "errorContentSubStream",
+      }
+    : null;
 
 const PasswordResponses = {
   NEED_PASSWORD: 1,
@@ -1152,7 +1127,6 @@ export {
   DocumentActionEventType,
   FeatureTest,
   FONT_IDENTITY_MATRIX,
-  FontType,
   FormatError,
   getModificationDate,
   getVerbosityLevel,
@@ -1175,7 +1149,6 @@ export {
   RenderingIntentFlag,
   setVerbosityLevel,
   shadow,
-  StreamType,
   string32,
   stringToBytes,
   stringToPDFString,
diff --git a/test/unit/api_spec.js b/test/unit/api_spec.js
index 4e84f5f76..933cd6130 100644
--- a/test/unit/api_spec.js
+++ b/test/unit/api_spec.js
@@ -17,7 +17,6 @@ import {
   AnnotationMode,
   AnnotationType,
   createPromiseCapability,
-  FontType,
   ImageKind,
   InvalidPDFException,
   MissingPDFException,
@@ -25,7 +24,6 @@ import {
   PasswordException,
   PasswordResponses,
   PermissionFlag,
-  StreamType,
   UnknownErrorException,
 } from "../../src/shared/util.js";
 import {
@@ -1846,11 +1844,6 @@ describe("api", function () {
       expect(downloadInfo).toEqual({ length: basicApiFileLength });
     });
 
-    it("gets document stats", async function () {
-      const stats = pdfDocument.stats;
-      expect(stats).toEqual(null);
-    });
-
     it("cleans up document resources", async function () {
       await pdfDocument.cleanup();
 
@@ -2761,24 +2754,6 @@ Caron Broadcasting, Inc., an Ohio corporation (“Lessee”).`)
       await loadingTask.destroy();
     });
 
-    it("gets document stats after parsing page", async function () {
-      await page.getOperatorList();
-      const stats = pdfDocument.stats;
-
-      const expectedStreamTypes = {
-        [StreamType.FLATE]: true,
-      };
-      const expectedFontTypes = {
-        [FontType.TYPE1STANDARD]: true,
-        [FontType.CIDFONTTYPE2]: true,
-      };
-
-      expect(stats).toEqual({
-        streamTypes: expectedStreamTypes,
-        fontTypes: expectedFontTypes,
-      });
-    });
-
     it("gets page stats after parsing page, without `pdfBug` set", async function () {
       await page.getOperatorList();
       expect(page.stats).toEqual(null);
diff --git a/test/unit/test_utils.js b/test/unit/test_utils.js
index 0987ed32a..846c2b6c8 100644
--- a/test/unit/test_utils.js
+++ b/test/unit/test_utils.js
@@ -16,7 +16,6 @@
 import { NullStream, StringStream } from "../../src/core/stream.js";
 import { Page, PDFDocument } from "../../src/core/document.js";
 import { assert } from "../../src/shared/util.js";
-import { DocStats } from "../../src/core/core_utils.js";
 import { isNodeJS } from "../../src/shared/is_node.js";
 import { Ref } from "../../src/core/primitives.js";
 
@@ -77,7 +76,6 @@ function buildGetDocumentParams(filename, options) {
 class XRefMock {
   constructor(array) {
     this._map = Object.create(null);
-    this.stats = new DocStats({ send: () => {} });
     this._newTemporaryRefNum = null;
     this._newPersistentRefNum = null;
     this.stream = new NullStream();