File size limit on the forum

In this reply, it is mentioned that we can upload videos that are up to 100 MB in size on the forum.
I thought the limit was 8 MB. That’s is great if it was raised to 100 MB

However if I try to upload a video that is more than 8 MB, I get this pop-up window:

So, according to this, the limit is indeed around 100 MB. But why is my 10 MB file rejected?

I don’t know. I will change the setting back to 8 since it did not work.