I just checked on Google, and there are more than 92 million usages - so far - of the passive-aggressive-leftist phrase "be kind".
The meaning of this term is best encapsulated by that fact that you can buy a 'pastel rainbow' birdemic face-mask featuring the slogan - printed in lower-case, girly-looking, faux-handwriting.
So what is the meaning of "be kind"?
In narrow terms "be kind" could be translated as "stop disagreeing with me, else I will report you" -
More broadly, it translates as "I submit (eagerly) to totalitarian evil - do thou likewise".