v1.21.0

What's Changed

Added

• Jinja2 Dependency: Added explicit jinja2>=3.0.0 requirement for HTML report template rendering

Changed

• USB Port Scanning: Background scanner now pre-fetches serial ports every 3 seconds, eliminating "Scanning ports..." delays in connection menus
• USB Connection Menu: Added "Refresh Ports" option and shows "No ports detected" when empty
• GUI Queue Polling: Reduced from 100ms to 50ms for faster response to device messages

Fixed

• Report Filename Sanitization: Serial numbers containing invalid characters (like "N/A") no longer create subdirectories - invalid filename characters are now replaced with dashes
• Report Error Messages: Now shows actual Python import errors when report modules fail to load, instead of generic "not found" messages
• CSV File Sync on Windows: Data logger now calls fsync before closing files to ensure Windows flushes data to disk before report generation
• GUI Thread Safety: Script completion callbacks now properly schedule Tkinter updates on the main thread, preventing potential race conditions
• Report Debug Logging: Enhanced logging for troubleshooting report generation (CSV paths, file locks, handler calls)

Full Changelog: ...v1.21.0