Obtain an ICoreWebView2Deferral object and put the event into a
deferred state. Use the ICoreWebView2Deferral object to complete the
window open request at a later time. While this event is deferred the
opener window returns a WindowProxy to an un-navigated window, which
navigates when the deferral is complete.
The D Programming Language's Unofficial Docs
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Obtain an ICoreWebView2Deferral object and put the event into a deferred state. Use the ICoreWebView2Deferral object to complete the window open request at a later time. While this event is deferred the opener window returns a WindowProxy to an un-navigated window, which navigates when the deferral is complete.