Having opened the file chooser dialog in IE,
self.webDiver.switch_to_alert().accept()
Tried the above line but does not click the open button.
IE Version 11.2580.14393.0;
Windows Server 2016 Standard
The dialog that gets displayed is "Choose File to Upload", this dialog has a File name text box with a Combobox + Open button as well as an Open button that is a SplitButtonControl with options to Open/Open readonly or save as previous version.
Edge and chrome version 83 alerts for a OAuth or Single Sign on User Credentials are a special case of Alert.
Dialog window is not part of the Browser, its a Operating system dialog (some technicalities are glossed over here) and launches in a separate process.
I was unable to find a Selenium method for interacting with Windows Dialog so used python uiautomation for windows instead:
window2 = uiautomation.WindowControl(searchDepth=1, ClassName='Credential Dialog Xaml Host')
window2.SetActive()
window2.SendKeys('username{TAB}password')
window2.ButtonControl(searchDepth=10, Name='OK').Click()