When I upgrade Laravel 6 to 7, I found out the following error.
Problem 1 - Root composer.json requires php-ffmpeg/binary-driver dev-master -> satisfiable by php-ffmpeg/binary-driver[dev-master]. - php-ffmpeg/binary-driver dev-master requires monolog/monolog ^1.3 -> found monolog/monolog[1.3.0, ..., 1.x-dev] but it conflicts with your root composer.json require (2.6.0).