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The API is no longer sending Cross-Origin Resource Sharing (CORS) headers after 180 calls
You can replicate it from any browser using the code below.
Every time I run it, it fetches 180 pages at an average rate of 5.51 calls per second.
On the 181st call I get: Cross-Origin Request Blocked
This affects all API calls to all sites and is wreaking havoc with multiple userscripts that rely on the API, but get a CORS error and will not process the response.