```
Last Exception Backtrace:
0 CoreFoundation 0x196d85e48 __exceptionPreprocess + 164 (NSException.m:202)
1 libobjc.A.dylib 0x19005b8d8 objc_exception_throw + 60 (objc-exception.mm:356)
2 UIKitCore 0x199277cbc -[UIViewController _presentViewController:withAnimationController:completion:] + 4080 (UIViewController.m:0)
3 UIKitCore 0x199276c10 __63-[UIViewController _presentViewController:animated:completion:]_block_invoke + 92 (UIViewController.m:8982)
4 UIKitCore 0x19929a598 -[_UIViewControllerTransitionCoordinator _applyBlocks:releaseBlocks:] + 240 (UIViewControllerTransitioning.m:1148)
5 UIKitCore 0x199208a48 -[_UIViewControllerTransitionContext _runAlongsideCompletions] + 140 (UIViewControllerTransitioning.m:380)
6 UIKitCore 0x199207ad8 -[_UIViewControllerTransitionContext completeTransition:] + 128 (UIViewControllerTransitioning.m:292)
7 Wikipedia 0x1030409b0 closure #2 in TableOfContentsAnimator.animateTransition(_:duration:animations:completion:) + 8 (TableOfContentsAnimator.swift:189)
8 Wikipedia 0x1030409b0 partial apply for closure #2 in TableOfContentsAnimator.animateTransition(_:duration:animations:completion:) + 32 (<compiler-generated>:0)
9 Wikipedia 0x10304e1a4 thunk for @escaping @callee_guaranteed (@unowned Bool) -> () + 40 (<compiler-generated>:0)
```
```
Last Exception Backtrace:
0 CoreFoundation 0x1bdef9f94 __exceptionPreprocess + 164 (NSException.m:202)
1 libobjc.A.dylib 0x1b704c3d0 objc_exception_throw + 60 (objc-exception.mm:356)
2 UIKitCore 0x1c0286d98 -[UIViewController _presentViewController:withAnimationController:completion:] + 4052 (UIViewController.m:0)
3 UIKitCore 0x1c02fcd94 __63-[UIViewController _presentViewController:animated:completion:]_block_invoke_2 + 56 (UIViewController.m:8992)
4 UIKitCore 0x1bff966e0 +[UIView(Animation) performWithoutAnimation:] + 76 (UIView.m:14792)
5 UIKitCore 0x1c0285d7c __63-[UIViewController _presentViewController:animated:completion:]_block_invoke + 208 (UIViewController.m:8990)
6 UIKitCore 0x1c0264158 -[UIViewController _performCoordinatedPresentOrDismiss:animated:] + 396 (UIViewController.m:9254)
7 UIKitCore 0x1c0034f7c -[UIViewController _presentViewController:animated:completion:] + 188 (UIViewController.m:9002)
8 UIKitCore 0x1c0034db8 -[UIViewController presentViewController:animated:completion:] + 164 (UIViewController.m:9198)
9 Wikipedia 0x104783510 closure #1 in ArticleTableOfContentsDisplayController.showModal(animated:) + 76 (ArticleTableOfContentsDisplayController.swift:94)
10 Wikipedia 0x104783510 partial apply for closure #1 in ArticleTableOfContentsDisplayController.showModal(animated:) + 108 (<compiler-generated>:0)
11 Wikipedia 0x104631438 closure #1 in ArticleViewController.getVisibleSection(with:) + 408 (ArticleViewController+TableOfContents.swift:15)
12 Wikipedia 0x1045bcd78 thunk for @escaping @callee_guaranteed (@in_guaranteed Any?, @guaranteed Error?) -> () + 120 (<compiler-generated>:0)
```