feat: Perfect Chrome 143 fingerprint matching with documentation sync

- Add Chrome-like HTTP/2 priority (weight=256, exclusive=1) in http2_logic.c
- Remove zlib from certificate compression, use Brotli only (per Chrome behavior)
- Add Chrome default headers to Session (sec-ch-ua, sec-fetch-*, priority)
- Update all documentation to reflect Chrome 143 as default profile
- Sync README and ReadTheDocs with actual code behavior:
  - Client and Session both default to http2=True
  - Certificate compression is Brotli only
  - Updated fingerprint characteristics (JA4, JA3N, Peetprint, Akamai)
- Fix test names to match http2=True default behavior

Author: arman-bd

README.md

@@ -124,7 +124,7 @@ httpmorph accurately mimics **Chrome 127-143** TLS and HTTP/2 fingerprints with:
 - **TLS 1.3** with correct cipher suites and extensions
 - **HTTP/2** with Chrome-specific SETTINGS frame and pseudo-header order
 - **Post-quantum cryptography** (X25519MLKEM768)
-- **Certificate compression** (Brotli, Zlib)
+- **Certificate compression** (Brotli)
 
 **Verify your fingerprint:**
 
@@ -148,19 +148,18 @@ All Chrome 127-143 profiles produce **exact JA4 matches** with real Chrome brows
 httpmorph supports HTTP/2 with an httpx-like API:
 
 ```python
-# Enable HTTP/2 for a client (default is False)
-client = httpmorph.Client(http2=True)
+# Both Client and Session default to HTTP/2 (http2=True) like Chrome
+client = httpmorph.Client()
 response = client.get('https://www.google.com')
 print(response.http_version)  # '2.0'
 
-# Enable HTTP/2 for a session
-session = httpmorph.Session(browser='chrome', http2=True)
+session = httpmorph.Session(browser='chrome')
 response = session.get('https://www.google.com')
 print(response.http_version)  # '2.0'
 
-# Per-request HTTP/2 override
-client = httpmorph.Client(http2=False)  # Default disabled
-response = client.get('https://www.google.com', http2=True)  # Enable for this request
+# Per-request HTTP/2 override (disable for specific request)
+client = httpmorph.Client()  # Defaults to HTTP/2
+response = client.get('https://example.com', http2=False)  # Disable for this request
 ```
 
 ### Custom Headers
@@ -440,7 +439,7 @@ pytest tests/ -v
 - HTTP/2 support via nghttp2
 - Inspired by Python's requests and httpx libraries
 - Chrome 127-143 fingerprint matching with perfect JA4, JA3N, and HTTP/2 Akamai fingerprints
-- Certificate compression support for Cloudflare-protected sites
+- Certificate compression (Brotli) for Cloudflare-protected sites
 
 ## FAQ
 
@@ -457,7 +456,7 @@ A: No, httpmorph is still in active development and not yet recommended for prod
 A: For most common use cases, yes! We've implemented the most widely-used requests API. Some advanced features may have slight differences.
 
 **Q: Does it work with Cloudflare-protected sites?**
-A: Yes! httpmorph supports certificate compression (Brotli, Zlib) which is required for many Cloudflare-protected sites. We successfully tested with icanhazip.com and postman-echo.com.
+A: Yes! httpmorph supports certificate compression (Brotli) which is required for many Cloudflare-protected sites. We successfully tested with icanhazip.com and postman-echo.com.
 
 **Q: How do I report a bug?**
 A: Please open an issue on GitHub with a minimal reproduction example and your environment details (OS, Python version, httpmorph version).

docs/source/advanced.rst

@@ -9,11 +9,11 @@ TLS Fingerprinting
 Browser-Specific Fingerprints
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-httpmorph generates accurate Chrome 142 TLS fingerprints with perfect JA3N, JA4, and JA4_R matching:
+httpmorph generates accurate Chrome 143 TLS fingerprints with perfect JA3N, JA4, JA4_R, and Akamai matching:
 
 .. code-block:: python
 
-   # Chrome 142 profile (default)
+   # Chrome 143 profile (default)
    session = httpmorph.Session(browser='chrome')
    response = session.get('https://example.com')
 
@@ -23,7 +23,7 @@ httpmorph generates accurate Chrome 142 TLS fingerprints with perfect JA3N, JA4,
    print('HTTP:', response.http_version)
 
    # Output example:
-   # JA3: 8e19337e7524d2573be54efb2b0784c9 (Chrome 142 normalized)
+   # JA3: dcefaf3f0e71d260d19dc1d0749c9278 (Chrome 143 normalized)
    # TLS: TLSv1.3
    # Cipher: TLS_AES_128_GCM_SHA256
    # HTTP: 2.0
@@ -53,7 +53,7 @@ Customize the User-Agent for different operating systems:
 GREASE Values
 ~~~~~~~~~~~~~
 
-Chrome 142 uses GREASE (Generate Random Extensions And Sustain Extensibility) values that are randomized per request to maintain TLS ecosystem extensibility:
+Chrome 143 uses GREASE (Generate Random Extensions And Sustain Extensibility) values that are randomized per request to maintain TLS ecosystem extensibility:
 
 .. code-block:: python
 

docs/source/api.rst

@@ -90,13 +90,13 @@ Client Class
 
 .. code-block:: python
 
-   client = httpmorph.Client(http2=False)
+   client = httpmorph.Client(http2=True)
 
-HTTP client for making requests.
+HTTP client for making requests. Defaults to HTTP/2 to match Chrome behavior.
 
 **Constructor Parameters:**
 
-* ``http2`` (bool) - Enable HTTP/2. Default: ``False``
+* ``http2`` (bool) - Enable HTTP/2. Default: ``True``
 
 **Methods:**
 
@@ -127,15 +127,15 @@ Session Class
 
 .. code-block:: python
 
-   session = httpmorph.Session(browser='chrome', os='macos', http2=False)
+   session = httpmorph.Session(browser='chrome', os='macos', http2=True)
 
-HTTP session with persistent cookies and headers.
+HTTP session with persistent cookies and headers. Sessions default to HTTP/2 to match Chrome browser behavior.
 
 **Constructor Parameters:**
 
-* ``browser`` (str) - Browser profile to mimic. Options: ``'chrome'``, ``'chrome142'``, ``'random'``. Default: ``'chrome'``
+* ``browser`` (str) - Browser profile to mimic. Options: ``'chrome'``, ``'chrome127'``-``'chrome143'``, ``'random'``. Default: ``'chrome'`` (Chrome 143)
 * ``os`` (str) - Operating system for User-Agent. Options: ``'macos'``, ``'windows'``, ``'linux'``. Default: ``'macos'``
-* ``http2`` (bool) - Enable HTTP/2. Default: ``False``
+* ``http2`` (bool) - Enable HTTP/2. Default: ``True`` (matches Chrome behavior)
 
 **Attributes:**
 
@@ -423,42 +423,55 @@ Browser Profiles
 
 Available browser profiles for ``Session(browser=...)``:
 
-Chrome 142
-~~~~~~~~~~
+Chrome 143 (Default)
+~~~~~~~~~~~~~~~~~~~~
 
-The default and most accurate browser profile, mimicking Chrome 142:
+The default and most accurate browser profile, mimicking Chrome 143:
 
 **Fingerprint Characteristics:**
 
-* **JA3N**: ``8e19337e7524d2573be54efb2b0784c9`` (perfect match)
-* **JA4**: ``t13d1516h2_8daaf6152771_d8a2da3f94cd`` (perfect match)
-* **JA4_R**: ``t13d1516h2_002f,0035,009c,...`` (perfect match)
+* **JA4**: ``t13d1516h2_8daaf6152771_e5627efa2ab1`` (perfect match)
+* **JA3N**: ``dcefaf3f0e71d260d19dc1d0749c9278`` (perfect match)
+* **Peetprint**: ``1d4ffe9b0e34acac0bd883fa7f79d7b5`` (perfect match)
+* **Akamai HTTP/2**: ``1:65536;2:0;4:6291456;6:262144|15663105|0|m,a,s,p`` (perfect match)
 * **TLS 1.3** with 15 cipher suites
 * **Post-quantum cryptography**: X25519MLKEM768 (curve 4588)
-* **Certificate compression**: Brotli, Zlib
+* **Certificate compression**: Brotli only
 * **GREASE**: Randomized per request
-* **HTTP/2**: Chrome-specific SETTINGS frame
+* **HTTP/2**: Chrome-specific SETTINGS frame, priority (weight=256, exclusive=1)
+* **Default headers**: sec-ch-ua, sec-fetch-*, accept-language, priority
 
 **User-Agent Variants:**
 
-* **macOS**: ``Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/142.0.0.0 Safari/537.36``
-* **Windows**: ``Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/142.0.0.0 Safari/537.36``
-* **Linux**: ``Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/142.0.0.0 Safari/537.36``
+* **macOS**: ``Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/143.0.0.0 Safari/537.36``
+* **Windows**: ``Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/143.0.0.0 Safari/537.36``
+* **Linux**: ``Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/143.0.0.0 Safari/537.36``
 
 **Usage:**
 
 .. code-block:: python
 
-   # Use Chrome 142 profile (default)
+   # Use Chrome 143 profile (default)
    session = httpmorph.Session(browser='chrome')
 
-   # Explicitly use Chrome 142
-   session = httpmorph.Session(browser='chrome142')
+   # Explicitly use Chrome 143
+   session = httpmorph.Session(browser='chrome143')
 
    # With specific OS
    session = httpmorph.Session(browser='chrome', os='windows')
 
+Chrome 127-142
+~~~~~~~~~~~~~~
+
+Older Chrome profiles are also available for compatibility testing:
+
+.. code-block:: python
+
+   session = httpmorph.Session(browser='chrome127')
+   session = httpmorph.Session(browser='chrome135')
+   # etc.
+
 Random
 ~~~~~~
 
-Randomly selects a browser profile for each session. Currently only Chrome 142 is available.
+Randomly selects a browser profile for each session from available Chrome profiles.

docs/source/quickstart.rst

@@ -102,12 +102,12 @@ Mimic Chrome browser with realistic fingerprints:
 
 .. code-block:: python
 
-   # Chrome browser profile (defaults to Chrome 142)
+   # Chrome browser profile (defaults to Chrome 143)
    session = httpmorph.Session(browser='chrome')
    response = session.get('https://example.com')
 
-   # Use specific Chrome version
-   session = httpmorph.Session(browser='chrome142')
+   # Use specific Chrome version (127-143 supported)
+   session = httpmorph.Session(browser='chrome143')
    response = session.get('https://example.com')
 
    # Random browser selection
@@ -118,9 +118,10 @@ The Chrome browser profile includes:
 * Chrome-specific User-Agent
 * Chrome-specific TLS cipher suites and extensions
 * Post-quantum cryptography (X25519MLKEM768)
-* Certificate compression (Brotli, Zlib)
-* Chrome-specific HTTP/2 settings
-* Perfect JA3N, JA4, and JA4_R fingerprint matching
+* Certificate compression (Brotli)
+* Chrome-specific HTTP/2 settings and priority
+* Perfect JA3N, JA4, JA4_R, and Akamai fingerprint matching
+* Chrome-like default headers (sec-ch-ua, sec-fetch-*, etc.)
 
 OS-Specific User Agents
 ~~~~~~~~~~~~~~~~~~~~~~~~
@@ -344,21 +345,22 @@ Upload files:
 HTTP/2
 ------
 
-Enable HTTP/2 support:
+Both Client and Session default to HTTP/2 to match Chrome behavior:
 
 .. code-block:: python
 
-   # For all requests in a client
-   client = httpmorph.Client(http2=True)
+   # Both Client and Session default to HTTP/2 (http2=True)
+   client = httpmorph.Client()
    response = client.get('https://www.google.com')
+   print(response.http_version)  # '2.0'
 
-   # For all requests in a session
-   session = httpmorph.Session(browser='chrome', http2=True)
+   session = httpmorph.Session(browser='chrome')
    response = session.get('https://www.google.com')
+   print(response.http_version)  # '2.0'
 
-   # Per-request override
-   client = httpmorph.Client(http2=False)
-   response = client.get('https://www.google.com', http2=True)
+   # Per-request override (disable HTTP/2 for specific request)
+   client = httpmorph.Client()  # Defaults to HTTP/2
+   response = client.get('https://example.com', http2=False)
 
 Check HTTP version:
 

src/core/http2_logic.c

@@ -348,17 +348,22 @@ int httpmorph_http2_request(SSL *ssl, const httpmorph_request_t *request,
         data_prd_ptr = &data_prd;
     }
 
-    /* Set up priority spec if priority is configured */
+    /* Set up priority spec - Chrome uses weight=256, exclusive=1, depends_on=0 by default */
     nghttp2_priority_spec pri_spec;
     nghttp2_priority_spec *pri_spec_ptr = NULL;
 
-    if (request->http2_stream_dependency != 0 || request->http2_priority_weight != 16) {
-        /* Priority is configured - use it */
+    if (request->http2_stream_dependency != 0 || request->http2_priority_weight != 16 ||
+        request->http2_priority_exclusive) {
+        /* Priority is explicitly configured - use it */
         nghttp2_priority_spec_init(&pri_spec,
                                    request->http2_stream_dependency,
                                    request->http2_priority_weight,
                                    request->http2_priority_exclusive ? 1 : 0);
         pri_spec_ptr = &pri_spec;
+    } else {
+        /* Use Chrome default priority: weight=256, exclusive=1, depends_on=0 */
+        nghttp2_priority_spec_init(&pri_spec, 0, 256, 1);
+        pri_spec_ptr = &pri_spec;
     }
 
     /* Submit request with priority spec and data provider */
@@ -563,17 +568,22 @@ int httpmorph_http2_request_pooled(struct pooled_connection *conn,
         data_prd_ptr = &data_prd;
     }
 
-    /* Set up priority spec if priority is configured */
+    /* Set up priority spec - Chrome uses weight=256, exclusive=1, depends_on=0 by default */
     nghttp2_priority_spec pri_spec;
     nghttp2_priority_spec *pri_spec_ptr = NULL;
 
-    if (request->http2_stream_dependency != 0 || request->http2_priority_weight != 16) {
-        /* Priority is configured - use it */
+    if (request->http2_stream_dependency != 0 || request->http2_priority_weight != 16 ||
+        request->http2_priority_exclusive) {
+        /* Priority is explicitly configured - use it */
         nghttp2_priority_spec_init(&pri_spec,
                                    request->http2_stream_dependency,
                                    request->http2_priority_weight,
                                    request->http2_priority_exclusive ? 1 : 0);
         pri_spec_ptr = &pri_spec;
+    } else {
+        /* Use Chrome default priority: weight=256, exclusive=1, depends_on=0 */
+        nghttp2_priority_spec_init(&pri_spec, 0, 256, 1);
+        pri_spec_ptr = &pri_spec;
     }
 
     /* Submit request with stream-specific user data
@@ -764,17 +774,22 @@ int httpmorph_http2_request_concurrent(struct pooled_connection *conn,
         data_prd_ptr = &data_prd;
     }
 
-    /* Set up priority spec if priority is configured */
+    /* Set up priority spec - Chrome uses weight=256, exclusive=1, depends_on=0 by default */
     nghttp2_priority_spec pri_spec;
     nghttp2_priority_spec *pri_spec_ptr = NULL;
 
-    if (request->http2_stream_dependency != 0 || request->http2_priority_weight != 16) {
-        /* Priority is configured - use it */
+    if (request->http2_stream_dependency != 0 || request->http2_priority_weight != 16 ||
+        request->http2_priority_exclusive) {
+        /* Priority is explicitly configured - use it */
         nghttp2_priority_spec_init(&pri_spec,
                                    request->http2_stream_dependency,
                                    request->http2_priority_weight,
                                    request->http2_priority_exclusive ? 1 : 0);
         pri_spec_ptr = &pri_spec;
+    } else {
+        /* Use Chrome default priority: weight=256, exclusive=1, depends_on=0 */
+        nghttp2_priority_spec_init(&pri_spec, 0, 256, 1);
+        pri_spec_ptr = &pri_spec;
     }
 
     /* Submit stream to session manager (non-blocking) */

src/core/tls.c

@@ -144,12 +144,11 @@ int httpmorph_configure_ssl_ctx(SSL_CTX *ctx, const browser_profile_t *profile)
     }
 
     /* Enable compress_certificate extension (0x001b) only if profile includes it.
-     * Chrome advertises brotli (2) and zlib (1) decompression support.
-     * We provide actual decompression functions for servers that send compressed certs.
+     * Chrome 143+ only advertises brotli (2) decompression support, NOT zlib.
+     * We provide actual decompression function for servers that send compressed certs.
      * The compress function is NULL since clients don't compress certificates. */
     if (has_compress_cert) {
         SSL_CTX_add_cert_compression_alg(ctx, TLSEXT_cert_compression_brotli, NULL, cert_decompress_brotli);
-        SSL_CTX_add_cert_compression_alg(ctx, TLSEXT_cert_compression_zlib, NULL, cert_decompress_zlib);
     }
 
     /* Force AES hardware preference to match Chrome's cipher order (AES-GCM before ChaCha20)

src/httpmorph/_client_c.py

@@ -654,14 +654,35 @@ def parse_set_cookie(self, set_cookie_header):
 class Session:
     """HTTP session with persistent fingerprint"""
 
+    # Chrome-like default headers for fingerprint matching
+    _CHROME_DEFAULT_HEADERS = {
+        # Client Hints (Chrome 143)
+        "sec-ch-ua": '"Chromium";v="143", "Google Chrome";v="143", "Not-A.Brand";v="24"',
+        "sec-ch-ua-mobile": "?0",
+        "sec-ch-ua-platform": '"macOS"',
+        # Fetch Metadata
+        "sec-fetch-dest": "document",
+        "sec-fetch-mode": "navigate",
+        "sec-fetch-site": "none",
+        "sec-fetch-user": "?1",
+        # Standard headers
+        "accept": "text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.7",
+        "accept-language": "en-US,en;q=0.9",
+        "cache-control": "max-age=0",
+        "upgrade-insecure-requests": "1",
+        # HTTP/2 Priority header (Chrome 143 style)
+        "priority": "u=0, i",
+    }
+
     def __init__(self, browser="chrome", http2=True, os="macos"):
         if not HAS_C_EXTENSION:
             raise RuntimeError("C extension not available")
         self._session = _httpmorph.Session(browser=browser, os=os)
         self.browser = browser
         self.os = os
         self.http2 = http2  # HTTP/2 enabled flag
-        self.headers = {}  # Persistent headers
+        # Initialize with Chrome-like default headers
+        self.headers = self._CHROME_DEFAULT_HEADERS.copy()
         self._cookies = CookieDict(self._session.cookie_jar)
 
     def __del__(self):