Bug overview description.
When viewing a Pool, the link in the header that goes to a Pool's reordering page (URL scheme below) for is absent if the Pool has at least 101 posts.
What part(s) of the site page(s) are affected?
Any individual Pool's page.
What is the expected behavior?
The link that says "Order" appears as the penultimate option in the header, between "History" and "Report".
What actual behavior is given instead?
"Order" is removed entirely. (Note that the reordering page is still available for all pools regardless of post count by manually adding /order/edit at the end of the Pool's URL, even those that have reached the one thousand  post limit.)
Time of incident (if applicable).
Found out about this at approximately 11:00 PM EDT on September 15, 2020. (UTC−4)
Can you reproduce the bug every time?
Yes; just viewing any Pool with over 100 posts will have the link missing.
What steps did you take to replicate this bug?
Made mostly redundant by the previous question; I was trying to edit this Pool, which has 111 posts as of this writing. This Pool has 101 posts, with the link removed, while this Pool has 100 posts, and thus shows the link.
Errors or other messages returned (if any).