sli.mg is the new imgur for /r/the_donald, and other subs whose content imgur regularly censors. I haven't really seen it used "in the wild" on more mainstream subs. It does have a nice, clean and minimalistic interface, similar to what imgur used to have.
It's like on Facebook - if something gets reported enough times on imgur it get's auto-censored until it maybe is manually restored by a imgur employee.
Because of that a lot of relatively benign Trump content gets censored on imgur because a lot of people find even his name to be offensive. Some even think his name is violence.
Not racial hatred, images of Robert Byrd kissing Hillary Clinton will get censored. Basically anything that is a joke at the expense of Hillary Clinton will get removed.
