What is the meaning of 'though'?

Okay, of course I've used different popular online dictionaries and the translation makes sense in the most cases.

Sometimes I find usages of 'though' where I don't get the meaning of the word.

An example I've found on twitter

That face, though. [Image of a dog looking weird]

The tweet came without any context or conversation.

When I translate this example to my native language - german - this makes absolutely no sense. At least for me.

So is the above usage some kind of slang?
What is the meaning of though in this case?

For the completeness an example that makes absolutely sense for me

Though he tried very hard, he failed the course.

Solution 1:

In this case, though is being used as an adverb.

As my New Oxford American Dictionary tells it:

though: adv. however (indicating that a factor qualifies or imposes restictions on what was previously said).

So in this case, you can think of it as such:

• Person A: [Picture of dog] _{(thinking: Man this dog is ugly!)}
• Person B: Cute face though _{(thinking: Yeah, he's ugly but/however his face is really cute)}

In other words, he's ugly, but we're going to limit his ugliness to everything but his face.

In your example, since person B just says "that face though", it's left to the reader to infer the cuteness/silliness/ugliness/craziness that is different between the face and the rest of the dog — presumably evident enough from the picture.