• Added $fileOpenMode param to StreamHandler to define a custom fopen mode to open the log file (#1913)
• Fixed PHP 8.4 deprecation notices (#1903)
• Added ability to extend/override IntrospectionProcessor (#1899)
• Added $timeout param to ProcessHandler to configure the stream_select() timeout to avoid blocking too long (default is 1.0 sec) (#1916)
• Fixed JsonFormatter batch handling to normalize records individually to make sure they look the same as if they were handled one by one - this leads to JsonFormatter::normalizeRecord now possibly returning stdClass instances instead of [] for empty context/extra data which may cause issues if you extend normalizeRecord, see https://github.com/Seldaek/monolog/pull/1906#issuecomment-2500046724 (#1906)
• Fixed StreamHandler handling of write failures so that it now closes/reopens the stream and retries the write once before failing (#1882)
• Fixed StreamHandler error handler causing issues if a stream handler triggers an error (#1866)
• Fixed StreamHandler::reset not closing the stream, so that it would fail to write in some cases with long running processes (#1862)
• Fixed RotatingFileHandler issue where rotation does not happen in some long running processes (#1905)
• Fixed JsonFormatter handling of incomplete classes (#1834)
• Fixed RotatingFileHandler bug where rotation could sometimes not happen correctly (#1905)

Full Changelog: https://github.com/Seldaek/monolog/compare/3.7.0...3.8.0