When a Switch Control user selects to browse the web view, the switch control cursor does not go just over the visible parts of the article but also over the parts that are covered by the navigation bar and the toolbar. This means that while the user reads an article, the Switch Control cursor keeps selecting elements that the user cannot see.
Also, when the user invokes an action on such an element that is covered e.g. by the toolbar, the action is not actually invoked on the UIWebView element, but on the covering toolbar. This can be very confusing, especially in situation when the selected element has roughly the dimensions of the toolbar. The user will either not understand why he is unable to choose a specific element in the toolbar or he will try to choose one and the action will actually be invoked on another.
See the attached screenshot where the selection is actually a link in the article although it looks like items of the toolbar are selected (although it looks like three items are selected at once, which is nonsense). Invoking the Touch action would probably open Languages as that is an element that is in the middle of the selection.
(Switch Control is an iOS assistive technology for severely paralyzed people or people suffering similar disabilities who cannot control the device in traditional ways and must rely on control by a single switch or a small number of switches (e.g. pressing a switch by palm of hand, activating a switch by winking or tilting their head to a side).)
This happens also in my demo app which has nothing but the navigation bar, tab bar and a UIWebView with a Wikipedia article loaded, so this might also be a UIWebView bug or a Switch Control bug.