It won't work with that link, it has to end with .gif

You can try pasting this one in your profile instead:
https://64.media.tumblr.com/e1e53f95275bda07a5785c82639c3f7e/tumblr_nuy0hzvsfT1uwzy53o1_400.gif

got this link from ItzOrangey's profile, don't tell

click the photo image while writing, next to the cool S

 as an example

You can try putting tje provided link in image tags [​*img].....[​*/img] (without the * characters) or using the "Insert/edit Media" button (7^th from left which does this automatically).


Given that this fails, I would suggest hosting the link at some other site (apparently this link is being blocked when used here).

Imgur is a common choice for free image hosting, but there are many options if you want to do a bit of research…