The iOS Safari keyboard scroll bug, fixed with one line of CSS

If you build a full-screen mobile editor as a position: fixed overlay with a fixed toolbar on top and a nav bar on the bottom , iOS Safari will happily scroll your entire chrome off-screen the moment the soft keyboard opens — but only when the content is short . The fix isn't a JavaScript viewport dance. It's one line: .editor .ProseMirror { padding-bottom : 60vh ; } Give the inner scroll container something to scroll , and iOS keeps the scroll inside it instead of falling back to scrolling the document (which drags your "fixed" elements along). No html / body locking required. I hit this while building the mobile editor for PenPage , a local-first WYSIWYG markdown notes app (React + TipTap/ProseMirror). Everything below is verified on a real iOS device. The setup Picture a mobile note editor that takes over the whole screen: ┌──────────────────────────┐ │ Toolbar (absolute,top) │ ← stays put ├──────────────────────────┤ │ │ │ Editable content │ ← scrolls │ (overflow-y: auto) │ │ │ ├──────────────────────────┤ │ Nav bar (absolute,bottom)│ ← stays put └──────────────────────────┘ The outer container is position: fixed; inset: 0 . The toolbar and nav bar are position: absolute inside it. The middle is the only thing that scrolls. Standard app-shell layout. Works great on desktop and Android. The symptom Tap into the editor, the iOS keyboard slides up, and: Long document (taller than the viewport): perfect. The content scrolls under the keyboard, the toolbar and nav bar stay nailed in place. Short document (shorter than the viewport): broken. Trying to scroll drags the whole screen — toolbar and nav bar included — as if the entire fixed overlay were a normal scrolling page. That "only when short" detail is the whole story. The root cause This is the long tail of WebKit bug #191204 : when the soft keyboard appears, iOS Safari's layout viewport gets shorter than the visual viewport , and the document itself becomes scrollable by the keyboard's height. Worse, in that stat