WebContent / GPU process crash on iPhone 15 (iOS 26.4); stable on iPad (iOS 26.4))

Summary
Our app’s WKWebView triggers a WebContent / GPU process crash on iPhone 15 running iOS 26.4. The same flow works on iPad running iOS 26.4.

Environment

  • Failing: iPhone 15, iOS 26.4
  • Working: iPad, iOS 26.4
  • Web stack: WKWebView / WebKit (Safari & Web)

What we see
The WKWebView web process terminates; logs show WebProcess and GPU process exits, followed by RBS assertion failures and (in one WebContent process) repeated containermanagerd XPC invalidation.

Expected
Web content loads and remains stable like on iPad 26.4.

Actual
Web process crashes; page goes blank or WebView recovers only after reload.


Logs

0x10715d518 - [pageProxyID=14, webPageID=15, PID=3629] WebPageProxy::dispatchProcessDidTerminate: reason=Crash\
0x10715ce18 - [pageProxyID=22, webPageID=23, PID=3629] WebPageProxy::dispatchProcessDidTerminate: reason=Crash\
0x1480f01e0 - GPUProcessProxy::didClose:\
0x1480f01e0 - GPUProcessProxy::gpuProcessExited: reason=Crash\
0x14808c640 - [PID=3633] WebProcessProxy::gpuProcessExited: reason=Crash\
0x14808cb80 - [PID=3634] WebProcessProxy::gpuProcessExited: reason=Crash\
WebContent[3633] 0x10d07ebc0 - GPUProcessConnection::didClose\
Error acquiring assertion: <Error Domain=RBSAssertionErrorDomain Code=2 "Specified target process 3630 does not exist" UserInfo=\{NSLocalizedFailureReason=Specified target process 3630 does not exist\}>\
0x148128600 - ProcessAssertion::acquireSync Failed to acquire RBS assertion 'XPCConnectionTerminationWatchdog' for process with PID=3630, error: (null)\
WebContent[3634] XPC connection to containermanagerd invalidated. Retry attempt 1 of 6\
WebContent[3634] XPC connection to containermanagerd invalidated. Retry attempt 2 of 6\
WebContent[3634] XPC connection to containermanagerd invalidated. Retry attempt 3 of 6\
WebContent[3634] XPC connection to containermanagerd invalidated. Retry attempt 4 of 6\
WebContent[3634] XPC connection to containermanagerd invalidated. Retry attempt 5 of 6\
WebContent[3634] XPC connection to containermanagerd invalidated. Retry attempt 6 of 6\
WebContent[3634] _container_query_get_result_at_index: error = 2\uc0\u8594 (51) XPC_INVALID_REPLY;\
WebContent[3634] container_system_group_path_for_identifier: error = ((container_error_t)51) XPC_INVALID_REPLY\
WebContent[3634] 0x11107ebc0 - GPUProcessConnection::didClose\

Please file an issue using Feedback Assistant, which we need to analyze logs. Please also provide details of how the problem can be reproduced (e.g. which app to test).

WebContent / GPU process crash on iPhone 15 (iOS 26.4); stable on iPad (iOS 26.4))
 
 
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