onEdit() trigger couldn't be used: Exception: You do not have permission to call SpreadsheetApp.openById. Required permissions: https://www.googleapis.com/auth/spreadsheets

[TsvetkovT]

More context: When I add it as a library and want to call ex. onEdit(e), it returns a permission error:
"Exception: You do not have permission to call SpreadsheetApp.openById. Required permissions: https://www.googleapis.com/auth/spreadsheets"

The permission scope https://www.googleapis.com/auth/spreadsheets is already in the application.json file.

[TsvetkovT]

The root cause is: SpreadsheetApp.openById(optKey) function

[andrewroberts]

onEdit is a simple trigger that doesn't have permission to access other spreadsheets. You will need to set up a "installable" onEdit for this to work.