Riddle: will you Get it In a Blue moon?
Who am I?
I am not valid in any language but can be found in the dictionary.
You can't say me and you can't understand me.
A doctor cannot help you but doctor is something that should give you a start.
I can be QWERTY and ASDFGH.
It is me if you try to write
riddleand really write
I am in this post.
So I am asking you: Who am I?
Okay, I am giving you a hint:
If your reputation is a bug, you can remove me from posts, here at SE.
And I give you an other hint, I already gave in the comments:
Hint 2: (I changed something)
The title is a BIG hint to start with.