Still having this issue.

Today I tried logging out of the forums then viewing the problem thread and was able to see the whole thread right to the end, though it still wouldn't take me to the end initially, I had to click other links to get to the end successfully.

Firstly I logged out from the forum.
After logout clicked Go to Forums Index.
Clicked the Garmin header up near the top.
Scrolled in the Garmin section to find the stickied Universal Firmware Patcher thread.
Clicked on the last post icon, currently
Link URL:
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.
Instead of taking me to the last post in that thread it took me to the top of page 31, showing Results 301 to 310 of 1238.
Then I clicked the "Last>>" link and it took me to the top of the last page correctly, and the whole page was viewable as it should be, except of course for links posted by others as I was logged out.

So, while still on the page with it showing correctly I logged in again, and after login the redirect took me to how it was before, not displaying correctly, only post #1220 visible, unable to access any post after that one in that thread, no quick reply box or anything else visible a the bottom, exactly the same as the image in this thread's first post...