Hi @YUNHEE CHO ,
Is communication between Edge and IE Mode using postMessage() impossible?
As far as I know this is not possible, they actually run in different browsers.
If it is impossible, is there any other way to communicate except setting two windows running in the same mode?
You could try sharing cookies between Edge and IE mode, I think it might work for you. It is implemented through group policy configuration, you can refer to related documents: How cookie sharing works and Configure Edge IE mode policy.
Regardless of browser's IE-mode setting, is there a way to open a pop-up in a specific mode (IE compatible or not) by programming ?
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