This is all with the demobrowser:

• When going to chrome://crash in a new tab without any history, we get a reload loop (which is what I'd expect because the demobrowser just calls reload() on crashes)
• When trying to close the tab in the reload loop, it either won't work, will SIGTRAP/abort with [13295:13295:0208/001649:FATAL:render_widget_host_impl.h(520)] Check failed: in_flight_event_count_ > 0 (0 vs. 0) (stack)
• When doing the same on a page without history, the page which was loaded before is reloaded, which seems wrong.
• When changing the code (in WebView::WebView in webview.cpp) to do setHtml("foo"); instead of reload(); and visiting the URL in an existing tab, there's a segfault in the main process (stack on 5.8). I think this one is fixed by https://codereview.qt-project.org/#/c/181111/ though.