You can create a symbolic link as follows
$cd ~/Downloads/Xcode\ 12/Xcode-beta\ 3.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator.sdk/Developer/Library/Frameworks
$mv XCTest.framework XCTest.framework.old
$ln -s ../../../../../Library/Frameworks/XCTest.framework .
BayAreaDeveloper
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// [NSClassFromString(class) respondsToSelector:NSSelectorFromString(sel)] i get false
Did you build with Xcode 11 then and run on iOS 14 device ?