Hi sixer,
I am sorry to hear that the plugin caused problems. If you are able to provide us with more details then that would be very helpful. We do our best to make the plugin as stable as possible.
Can you please describe what you mean with a “crash”? Do you perhaps mean a Flash of Unstyled Content as caused by an empty Critical CSS configuration?
A future update will disable critical CSS by default so that an FOUC will not occur directly after installation.
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