Created attachment 268854 [details] GIF video demonstrating the bug Original Bootstrap bug report: https://github.com/twbs/bootstrap/issues/18859 iOS version: 9.2 Hardware: iPhone 6S Plus Device orientation: Landscape Steps to reproduce: 1. Open Safari 2. Rotate the screen so it's in Landscape orientation 3. Navigate to a webpage 4. Open a new tab 5. Navigate to http://getbootstrap.com/javascript/#modals-sizes 6. Ensure that Safari's tabs bar is visible. (If it's not, scroll down and then up so it becomes visible.) 7. Tap either the "Large modal" or "Small modal" button Expected result: The position:fixed Bootstrap modal element should be visible and positioned within the bounds of the visual viewport Actual result: The position:fixed Bootstrap modal element isn't visible. To bring it into view, you must scroll the page down (and thus cause the tabs bar to hide). Additional notes: This bug only occurs when Safari's tabs bar is visible. (And thus it never occurs when in Portrait orientation.) If you hide the tabs bar (by scrolling down) before tapping the button, this bug doesn't occur. If the device is in Landscape orientation but has no other tabs open, this bug doesn't occur. This bug doesn't occur in OS X Safari 9.0.2.