It's not really a bug in the sense that I don't think it causes any issues right now, but it has the potential to cause a significant slowdown and should be fixed.
I haven't checked thoroughly enough to determine whether it doubles the request for every individual series page: page=1, page=2, page=3, page=4, or if it only affects the first page, which is possible. However, based on the screenshot, there are three requests that could be combined into a single request.
