After installing macOS Big Sur, you may run into issues getting Flutter set back up for development. Due to the security enhancements added to Catalina and increased in Big Sur, you may run into macOS blocking the execution of some development tools like Flutter and Dart.
If you run into the error message: “dart” can’t be opened because Apple cannot check it for malicious software.
You simply need to:
- Open system preferences/Security & Privacy/General
- Unlock by clicking the clock in the bottom left and enter your admin password
- Where it has the warning that “dart” was blocked, click “allow anyway”