Post with 238 notes

Ok so this is silly. I uploaded it as a TXT post and it works (thanks un-gif-dans-ta-gueule). Why would Tumblr accept the same image uploaded through a different post type?
Photo with 124 notes
Ok so I get the infamous “Error Uploading Photo” when I try to upload the original color version of this GIF so here is a black and white version that passed. I know about the saturation reduction but it only works sometimes and sometimes you just don’t want to change/ruin a GIF.
Here is the original color GIF uploaded somewhere else.
Download it and try posting it. This is a few months old problem so after all this time is there ANY concrete technical explanation why this color GIF is not accepted? Does anybody have any ideas why this is happening?