This can happen if you modified the bitrise.yml / workflow configuration in a way which crashes the Workflow Editor UI.
If this would happen please contact us so we can fix the issue in the UI code,
then you can fix the bitrise.yml through our API.
You can find an example of how the API works on GitHub.
In short, you can use a simple curl call to download & to upload an app’s config / bitrise.yml to bitrise.io.
With the Bitrise API you can download the bitrise.yml from bitrise.io even if it breaks the Workflow Editor UI,
fix it locally and then upload the fixed bitrise.yml with another API call. For this all you need is a Personal Access Token, which you can generate on your account’s security tab.
To download the bitrise.yml please check the related section of the Bitrise API documentation.
Save the bitrise.yml into a file, fix it, then you can upload it with another curl call.
To upload the bitrise.yml please also follow the related part of the Bitrise API documentation.
Note: make sure that you set the right path/to/bitrise.yml - specify the path of
the bitrise.yml file where you saved the fixed bitrise.yml!