Posting a Person’s content without their Permission is just plain Rude.
If you really like a person’s content, you should take a Direct Link to their page, and ask for people to Support them and give encouraging comments. Not take it as your own. Sure, saving the photo/video/gif and Submitting it elsewhere with credit is appreciated. But STILL ask If you can Submit it in other places. Direct links would be more helpful. People who create content need the Views, and Likes on THEIR page, not yours. It’s a Nice Gesture, but it can also hurt the person you stole from.
but Please for the Love of God, It’s not hard to ask the Creator for Permission. Support them, Don’t steal.