The 5.1.1b series has been released as 5.2 due to the scope of changes.
Major improvements
- Faster and more reliable connections to dual-stack hosts using Happy Eyeballs (RFC 8305) connection establishment
- Forward 1xx interim responses, including 103 Early Hints, recorded as linked transactions
- Many HTTP/2 proxying correctness and robustness improvements (see bug fixes)
Minor improvements
- New Unencrypted filter in the sequence view
- Improved sequence view filtering performance
- Improve expansion handling on the Structure view when using the filter
- New icons in the JSON and XML tree viewers
- Windows: JNA DLL is now codesigned
- Rewrite tool response status rewrite now works on HTTP2 responses
- Improved detection of text bodies for rewrite rules
- Rewrite the SSL certificate name when DNS Spoofing or the Rewrite tool changes the destination
- Recognise more TLS 1.3 draft minor versions and HTTP/3 draft version strings
- Propagate TCP half-close through tunnelled connections
- Flatlaf 3.7 for minor UI fixes & improvements on Linux and Windows
- New charles filter CLI subcommand for filtering requests and responses from saved Charles sessions
- --debug launch option to enable debug-level logging
- Allow saving the Error Log and streaming it to a file (right-click on Error Log)
Bug fixes
- HTTP2 fixes and improvements: fixes a hang when concurrent streams exhaust the connection window; improve handling of max concurrent streams; improve hung stream detection; fix protocol error when Charles forwards a reset after remote close; fix an issue where Charles created an extra DATA frame on some GET requests; protocol compliance improvements; early connection closed handling and reporting
- Block list tool no longer hangs the connection when it blocks HTTP2 requests
- Fix NullPointerException on Active Connections frame when under load
- Avoid displaying non-sensical TLS information for in-progress streams
- Fix CSS and feed validation
- Reduce flashing when switching between requests
- macOS: menu bar icon dims again when the menu bar is inactive
