When Apple unveiled iOS 26, it was instantly hailed as both phenomenal and controversial.
Phenomenal because of the polish and refinement Apple managed to inject into nearly every corner of the system, controversial because of the changes that once again pushed developers to rethink how their apps should look and behave. At the center of it all stood Liquid Glass, a design effect that captivated audiences at WWDC 2025.
Unlike the skeuomorphic era of iOS 6 or the flat minimalism of iOS 7, Liquid Glass took inspiration from the physics of light passing through viscous liquid, creating UI elements that shimmer with depth, translucence, and fluid distortion.
It’s more than a blur; it feels alive, shifting and refracting as content moves behind it.
While this new aesthetic was clearly a win for native iOS apps, but to those who work with webviews, which are the embedded browsers that power hybrid apps, they couldn’t help but feel left out.
For years, webviews have carried the stigma of being second-class citizens, never quite matching the polish of native UI. But a discovery tucked away in WebKit’s GitHub repository suggests Apple may be quietly closing that gap.
What they could, was to only recreate this effect. Designers and developers could only recreate the design language using standard CSS hacks like through backdrop-filters and SVG distortions, which are all pale in comparison to Apple’s optimized implementation.
But now, it's realized that a pull request spotted just after WWDC renamed "hosted blur" materials to reference "glass," and hidden within it was a private CSS property for this very Liquid Glass.
Unfortunately, the effect shouldn't work on the open web, and it's not designed to even work in a standard WKWebView out of the box. The property is gated behind a private setting in WKPreferences called useSystemAppearance, and unless that flag is toggled, the private CSS rule simply won’t render.
What this means, nobody should be able to use it.
However, a workaround is possible.
They can enable the hidden preference and applying -apple-visual-effect. This property, when paired with values like -apple-system-glass-material, allows web elements to adopt the very same Liquid Glass treatment native developers enjoy.
This will magically turn elements into using this private CSS property, rendering the true Liquid Glass in a webview, seamlessly blending with the rest of iOS 26’s interface.
While designers and developers creating their own using this can pretend to be native, some suggest that doing so wouldn't make the app authentic, or at least honest. This is why nobody should probably just slap a -webkit-liquid-glass on and call it a day.
Regardless, the cleverness of implementing it as a CSS property cannot be overstated.
Developers can gracefully fall back with a simple @supports rule, applying a semi-transparent background where the effect isn’t supported, and enabling Liquid Glass where it is possible. This suggests Apple wanted it to feel natural and declarative, not like a hack or workaround. It also hints at a broader philosophy: if webviews are to be taken seriously, they need the same visual vocabulary as native elements.
Critics argue that relying on private properties risks fragmenting the web, and they’re not wrong.
For now, this is an Apple-only affair, hidden behind private APIs that won’t pass App Store review. But the fact that the feature exists, points to a deeper truth: Apple must already be using it somewhere in its own apps.
In the end, Liquid Glass in WebKit is more like a hidden gem than a practical tool.
It’s a subtle clue about Apple’s design priorities, and how far the company is willing to go to blur, quite literally, the line between native and web, ensuring even the smallest details carry that unmistakable iOS polish.
Whether this private CSS property ever becomes standardized or remains locked in Cupertino’s walled garden, one thing is certain: Apple’s obsession with design, a hallmark since the earliest days of the Mac, is very much alive and it continues to shape not only how iOS looks, but how the web inside iOS feels.
For now, Liquid Glass in WebKit can only leave developers dreaming of a future where web and native interfaces no longer betray their differences, where the polish of iOS 26 becomes accessible to anyone building for the platform.
Until then, it stands as a reminder that innovation often hides in the fine print of changelogs, waiting to be uncovered by those curious enough to look.