I found that, if you change the Client Log Level to Debug or Trace, on the Console tab of Studio Pro, it will show the widget(s) where logger needs to be changed to mx.logger.
Robert answered a similar question perfectly:
This means you have a widget using “logger” instead of “mx.logger”. If you wrote the widget yourself, just change the code to use mx.logger and deploy a new version. However, if this is from a third party widget, you will need to see if there is a new version in the Marketplace to download and update.
Hope this helps you
This has been asked 3 months ago, and now I’ve got the same issue.
Here is how to find and fix this issue.
This issue is caused by some widgets are using `logger` in the code, which is outdated.
To find which one:
1: deploy the app for eclipse
2: open the app dir in eclipse or any other texteditor/IDE, VSCode is recommended, since it’s lighter
3: search the keyword logger, in VSCode, you can use regex search [^\.]logger to filter those ones already use mx.logger
4: only care about the js files
5: now that you know the widgets that still using this deprecated function, normally the file name is the widget name
6: goto the marketplace to search for the widget and download the latest version to replace it.