fix(session-replay): Include layer background color when checking if a view is opaque (#6629)

Author: itaybre

CHANGELOG.md

@@ -21,6 +21,9 @@
   - Improve transform calculations for views with custom anchor points
   - Fix axis-aligned transform detection for optimized opaque view clipping
 - Fix conversion of frame rate to time interval for session replay (#6623)
+- Change Session Replay masking to prevent semi‑transparent full‑screen overlays from clearing redactions by making opaque clipping stricter (#6629)
+  Views now need to be fully opaque (view and layer backgrounds with alpha == 1) and report opaque to qualify for clip‑out.
+  This avoids leaks at the cost of fewer clip‑out optimizations.
 
 ### Improvements
 

Sentry.xcodeproj/project.pbxproj

@@ -851,7 +851,6 @@
 		D4AF00212D2E92FD00F5F3D7 /* SentryNSFileManagerSwizzling.m in Sources */ = {isa = PBXBuildFile; fileRef = D4AF00202D2E92FD00F5F3D7 /* SentryNSFileManagerSwizzling.m */; };
 		D4AF00232D2E931000F5F3D7 /* SentryNSFileManagerSwizzling.h in Headers */ = {isa = PBXBuildFile; fileRef = D4AF00222D2E931000F5F3D7 /* SentryNSFileManagerSwizzling.h */; };
 		D4AF00252D2E93C400F5F3D7 /* SentryNSFileManagerSwizzlingTests.m in Sources */ = {isa = PBXBuildFile; fileRef = D4AF00242D2E93C400F5F3D7 /* SentryNSFileManagerSwizzlingTests.m */; };
-		D4AF7D262E9401EB004F0F59 /* SentryUIRedactBuilderTests+UIKit.swift in Sources */ = {isa = PBXBuildFile; fileRef = D4AF7D252E9401EB004F0F59 /* SentryUIRedactBuilderTests+UIKit.swift */; };
 		D4AF7D2A2E940493004F0F59 /* SentryUIRedactBuilderTests+Common.swift in Sources */ = {isa = PBXBuildFile; fileRef = D4AF7D292E940492004F0F59 /* SentryUIRedactBuilderTests+Common.swift */; };
 		D4AF7D2C2E9404ED004F0F59 /* SentryUIRedactBuilderTests+EdgeCases.swift in Sources */ = {isa = PBXBuildFile; fileRef = D4AF7D2B2E9404ED004F0F59 /* SentryUIRedactBuilderTests+EdgeCases.swift */; };
 		D4B0DC7F2DA9257A00DE61B6 /* SentryRenderVideoResult.swift in Sources */ = {isa = PBXBuildFile; fileRef = D4B0DC7E2DA9257200DE61B6 /* SentryRenderVideoResult.swift */; };
@@ -6171,7 +6170,6 @@
 				D45E2D772E003EBF0072A6B7 /* TestRedactOptions.swift in Sources */,
 				63FE720520DA66EC00CDBAE8 /* FileBasedTestCase.m in Sources */,
 				51B15F802BE88D510026A2F2 /* URLSessionTaskHelperTests.swift in Sources */,
-				D4AF7D262E9401EB004F0F59 /* SentryUIRedactBuilderTests+UIKit.swift in Sources */,
 				63EED6C32237989300E02400 /* SentryOptionsTest.m in Sources */,
 				7BBD18B22451804C00427C76 /* SentryRetryAfterHeaderParserTests.swift in Sources */,
 				7BD337E424A356180050DB6E /* SentryCrashIntegrationTests.swift in Sources */,

Sources/Swift/Core/Tools/ViewCapture/SentryUIRedactBuilder.swift

@@ -618,9 +618,58 @@ final class SentryUIRedactBuilder {
     }
 
     /// Indicates whether the view is opaque and will block other views behind it.
+    ///
+    /// A view is considered opaque if it completely covers and hides any content behind it.
+    /// This is used to optimize redaction by clearing out regions that are fully covered.
+    ///
+    /// The method checks multiple properties because UIKit views can become transparent in several ways:
+    /// - `view.alpha` (mapped to `layer.opacity`) can make the entire view semi-transparent
+    /// - `view.backgroundColor` or `layer.backgroundColor` can have alpha components
+    /// - Either the view or layer can explicitly set their `isOpaque` property to false
+    ///
+    /// ## Implementation Notes:
+    /// - We use the presentation layer when available to get the actual rendered state during animations
+    /// - We require BOTH the view and the layer to appear opaque (alpha == 1 and marked opaque)
+    ///   to classify a view as opaque. This avoids false positives where only one side is configured,
+    ///   which previously caused semi‑transparent overlays or partially configured views to clear
+    ///   redactions behind them.
+    /// - We use `SentryRedactViewHelper.shouldClipOut(view)` for views explicitly marked as opaque
+    ///
+    /// ## Bug Fix Context:
+    /// This implementation fixes the issue where semi-transparent overlays (e.g., with `alpha = 0.2`)
+    /// were incorrectly treated as opaque, causing text behind them to not be redacted.
+    /// See: https://github.com/getsentry/sentry-cocoa/pull/6629#issuecomment-3479730690
     private func isOpaque(_ view: UIView) -> Bool {
         let layer = view.layer.presentation() ?? view.layer
-        return SentryRedactViewHelper.shouldClipOut(view) || (layer.opacity == 1 && view.backgroundColor != nil && (view.backgroundColor?.cgColor.alpha ?? 0) == 1)
+
+        // Allow explicit override: if a view is marked to clip out, treat it as opaque
+        if SentryRedactViewHelper.shouldClipOut(view) {
+            return true
+        }
+
+        // First check: Ensure the layer opacity is 1.0
+        // This catches views with `alpha < 1.0`, which are semi-transparent regardless of background color.
+        // For example, a view with `alpha = 0.2` should never be considered opaque, even if it has
+        // a solid background color, because the entire view (including the background) is semi-transparent.
+        guard layer.opacity == 1 else {
+            return false
+        }
+
+        // Second check: Verify the view has an opaque background color
+        // We check the view's properties first because this is the most common pattern in UIKit.
+        let isViewOpaque = view.isOpaque && view.backgroundColor != nil && (view.backgroundColor?.cgColor.alpha ?? 0) == 1
+
+        // Third check: Verify the layer has an opaque background color
+        // We also check the layer's properties because:
+        // - Some views customize their CALayer directly without setting view.backgroundColor
+        // - Libraries or custom views might override backgroundColor to return different values
+        // - The layer's backgroundColor is the actual rendered property (view.backgroundColor is a convenience)
+        let isLayerOpaque = layer.isOpaque && layer.backgroundColor != nil && (layer.backgroundColor?.alpha ?? 0) == 1
+
+        // We REQUIRE BOTH: the view AND the layer must be opaque for the view to be treated as opaque.
+        // This stricter rule prevents semi‑transparent overlays or partially configured backgrounds
+        // (only view or only layer) from clearing previously collected redact regions.
+        return isViewOpaque && isLayerOpaque
     }
 }
 

Tests/SentryTests/ViewCapture/SentryUIRedactBuilderTests+Common.swift

@@ -152,6 +152,9 @@ class SentryUIRedactBuilderTests_Common: SentryUIRedactBuilderTests { // swiftli
 
         let opaqueView = UIView(frame: CGRect(x: 10, y: 10, width: 60, height: 60))
         opaqueView.backgroundColor = .white
+        opaqueView.isOpaque = true
+        opaqueView.layer.isOpaque = true
+        opaqueView.layer.backgroundColor = UIColor.white.cgColor
         rootView.addSubview(opaqueView)
 
         // View Hierarchy:
@@ -922,6 +925,9 @@ class SentryUIRedactBuilderTests_Common: SentryUIRedactBuilderTests { // swiftli
 
         let overView = UIView(frame: rootView.bounds)
         overView.backgroundColor = .black
+        overView.isOpaque = true
+        overView.layer.isOpaque = true
+        overView.layer.backgroundColor = UIColor.black.cgColor
         rootView.addSubview(overView)
 
         // View Hierarchy:
@@ -1208,7 +1214,7 @@ class SentryUIRedactBuilderTests_Common: SentryUIRedactBuilderTests { // swiftli
 
         // View Hierarchy:
         // ---------------
-        // == iOS 26 ==
+        // == iOS 26.1 - Xcode 26 ==
         // <UIView: 0x11b209710; frame = (0 0; 100 100); layer = <CALayer: 0x600000cd1440>>
         //   | <UISlider: 0x11b23e2e0; frame = (10 10; 80 20); opaque = NO; gestureRecognizers = <NSArray: 0x600000276be0>; layer = <CALayer: 0x600000ce80c0>; value: 0.000000>
         //   |    | <UIKit._UISliderGlassVisualElement: 0x11b25bdd0; frame = (0 0; 80 20); autoresize = W+H; layer = <CALayer: 0x600000cde0a0>>
@@ -1219,6 +1225,11 @@ class SentryUIRedactBuilderTests_Common: SentryUIRedactBuilderTests { // swiftli
         //   |    |    |    | <UIView: 0x11b22bf60; frame = (0 0; 37 24); autoresize = W+H; userInteractionEnabled = NO; layer = <CALayer: 0x600000ce9410>>
         //   |    |    |    |    | <UIView: 0x11b434710; frame = (0 0; 37 24); autoresize = W+H; userInteractionEnabled = NO; backgroundColor = <UIDynamicSystemColor: 0x600001749000; name = _controlForegroundColor>; layer = <CALayer: 0x600000cdd740>>
         //
+        // == iOS 26.1 - Xcode 16.4 ==
+        // <UIView: 0x10701dbf0; frame = (0 0; 100 100); layer = <CALayer: 0x600000cb96b0>>
+        //   | <UISlider: 0x100e28d30; frame = (10 10; 80 20); opaque = NO; layer = <CALayer: 0x600000cae490>; value: 0.000000>
+        //   |    | <_UISlideriOSVisualElement: 0x100f06990; frame = (0 0; 80 20); opaque = NO; autoresize = W+H; layer = <CALayer: 0x600000c05fe0>>
+        //
         // == iOS 18 & 17 & 16 ==
         // <UIView: 0x12ed12bc0; frame = (0 0; 100 100); layer = <CALayer: 0x600001de3540>>
         //   | <UISlider: 0x13ed0f7e0; frame = (10 10; 80 20); opaque = NO; layer = <CALayer: 0x600001df0020>; value: 0.000000>
@@ -1230,40 +1241,20 @@ class SentryUIRedactBuilderTests_Common: SentryUIRedactBuilderTests { // swiftli
         let masked = createMaskedScreenshot(view: rootView, regions: result)
 
         // -- Assert --
-        assertSnapshot(of: masked, as: .image, named: createTestDeviceOSBoundSnapshotName(name: "unmasked"))
-
-        // UISlider behavior differs by iOS version
-        if #available(iOS 26.0, *) {
-            // On iOS 26, UISlider uses a new visual implementation that creates clipping regions
-            // even though the slider itself is in the ignore list
-            let region0 = try XCTUnwrap(result.element(at: 0))
-            XCTAssertNil(region0.color)
-            XCTAssertEqual(region0.size, CGSize(width: 37, height: 24))
-            XCTAssertEqual(region0.type, .clipOut)
-            XCTAssertEqual(region0.transform, CGAffineTransform(a: 1, b: 0, c: 0, d: 1, tx: 10, ty: 8))
-
-            let region1 = try XCTUnwrap(result.element(at: 1))
+        if #available(iOS 26, *), isBuiltWithSDK26() {
+            // Only applies to Liquid Glass (enabled when built with Xcode 26+)
+            let region1 = try XCTUnwrap(result.element(at: 0))
             XCTAssertNil(region1.color)
             XCTAssertEqual(region1.size, CGSize(width: 80, height: 6))
             XCTAssertEqual(region1.type, .clipBegin)
             XCTAssertEqual(region1.transform, CGAffineTransform(a: 1, b: 0, c: 0, d: 1, tx: 10, ty: 17))
 
-            let region2 = try XCTUnwrap(result.element(at: 2))
+            let region2 = try XCTUnwrap(result.element(at: 1))
             XCTAssertNil(region2.color)
-            XCTAssertEqual(region2.size, CGSize(width: 0, height: 6))
-            XCTAssertEqual(region2.type, .clipOut)
+            XCTAssertEqual(region2.size, CGSize(width: 80, height: 6))
+            XCTAssertEqual(region2.type, .clipEnd)
             XCTAssertEqual(region2.transform, CGAffineTransform(a: 1, b: 0, c: 0, d: 1, tx: 10, ty: 17))
-
-            let region3 = try XCTUnwrap(result.element(at: 3))
-            XCTAssertNil(region3.color)
-            XCTAssertEqual(region3.size, CGSize(width: 80, height: 6))
-            XCTAssertEqual(region3.type, .clipEnd)
-            XCTAssertEqual(region3.transform, CGAffineTransform(a: 1, b: 0, c: 0, d: 1, tx: 10, ty: 17))
-
-            // Assert that there are no other regions
-            XCTAssertEqual(result.count, 4)
         } else {
-            // On iOS < 26, UISlider is completely ignored (no regions)
             XCTAssertEqual(result.count, 0)
         }
     }
@@ -1469,6 +1460,17 @@ private class TestGridView: UIView {
         ctx.setFillColor(UIColor.orange.cgColor)
         ctx.fill(CGRect(x: midX, y: midY, width: bounds.width - midX, height: bounds.height - midY))
     }
+    
+}
+
+private func isBuiltWithSDK26() -> Bool {
+    guard let value = Bundle.main.object(forInfoDictionaryKey: "DTXcode") as? String else {
+        return false
+    }
+    guard let xcodeVersion = Int(value) else {
+        return false
+    }
+    return xcodeVersion >= 2_600
 }
 
 #endif // os(iOS) && !targetEnvironment(macCatalyst)