I am facing similar issue, This happens when my XCUItest script uninstalls and reinstalls test application amid a single run.
2021-03-12 19:19:57.675873+0530 UITests-Runner[10864:1037908] * Assertion failure in -[XCTFuture _waitForFulfillment], XCTFuture.m:158
2021-03-12 19:19:58.359629+0530 UITests-Runner[10864:1037908] * Assertion failure in -[XCTActivityRecordStack didFinishActivity:testCase:], XCTActivityRecordStack.m:64
To me looks like Xcode issue (probably introduced since Xcode 12 and above).
I am using Xcode 12.3.
mbsmarty
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Any update/fix for this issue?
I find this issue whenever my script tries to uninstall and install the test app within same test run.