Some of these “gifs” need to be pasted in as pictures, some as media.
Just depends on the media type.
Usually I try inserting as a pic, if it fails... I try media. If that doesn’t work, we don’t have the decoder in our software.
See all that garbage after the letters "gif" up there? Erase them, and then post the rest as a link in the "insert image" link button. All images that you find can't have any characters after the letters GIF, or they won't load.