I have tried to open this blog: https://mirror.codeforces.com/blog/entry/124138 which is linked to the Goodbye 2023 round as the tutorial. But when I open this link (and I believe this is for more people), a pop-up appears "Can't find this topic". Other blogs where this also happens include: https://mirror.codeforces.com/blog/entry/124143. Why is this happening? I've deleted codeforces cookies, tried a different webbrowser, but that didn't help.