Could we do something like not destroy this style data is we're shutting down? It'll be a little tricky because we do need to destroy it in debug builds for leak checking purposes. The stacks I've seen are inside mozilla::dom::BrowserChild::RecvDestroy() so it should be possible to detect.
Bug 1613797 Comment 8 Edit History
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Could we do something like not destroy this style data if we're shutting down? It'll be a little tricky because we do need to destroy it in debug builds for leak checking purposes. The stacks I've seen are inside mozilla::dom::BrowserChild::RecvDestroy() so it should be possible to detect.