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<b><a class="bz_bug_link
bz_status_NEW "
title="NEW - Web Inspector: Issues inspecting the inspector, pausing on breakpoints causes content to not load"
href="https://bugs.webkit.org/show_bug.cgi?id=157198#c2">Comment # 2</a>
on <a class="bz_bug_link
bz_status_NEW "
title="NEW - Web Inspector: Issues inspecting the inspector, pausing on breakpoints causes content to not load"
href="https://bugs.webkit.org/show_bug.cgi?id=157198">bug 157198</a>
from <span class="vcard"><a class="email" href="mailto:joepeck@webkit.org" title="Joseph Pecoraro <joepeck@webkit.org>"> <span class="fn">Joseph Pecoraro</span></a>
</span></b>
<pre>I think I found the issue.
When the Web Inspector itself is paused but the Inspected Page is not paused, then when the Web Inspector Process goes to dispatch a message (evaluating script in the page) we fail.
Here is the chain of events:
InspectorProcess
-> sendMessageToBackend( "Network.getResponseBody" )
-> send Messages::WebInspector::SendMessageToBackend to WebContentProcess
InspectorProcess
-> PAUSE evaluating Web Inspector page JavaScript
-> Run Nested Run Loop
WebContentProcess
- receive Messages::WebInspector::SendMessageToBackend message
-> InspectorNetworkAgent::getResponseBody
-> InspectorBackendDispatcher::sendMessageToFrontend
-> WebInspector::sendMessageToFrontend (WebKit2 FrontendClient)
-> send Messages::WebInspectorUI::SendMessageToFrontend to InspectorProcess
InspectorProcess* (in nested runloop)
- receive Messages::WebInspectorUI::SendMessageToFrontend
-> WebInspectorUI::sendMessageToFrontend
-> WebInspectorFrontendAPIDispatcher::dispatchMessageAsync
-> ScriptController::executeScript
-> Cannot execute script, we are paused, the message NEVER gets sent
So, in this scenario, WebInspectorFrontendAPIDispatcher can queue up messages while the inspector page is paused (something that we don't normally expect).
This also sheds light on another possible issue of APIs (JSContext / WKWebView) attempting to evaluating JavaScript on a paused page will just have their scripts dropped on the floor. However, that has always been the case, so I'm going to address that now.</pre>
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