"Belong to" or "belong on"

When I was flagging a post on English Language & Usage Stack Exchange, I found this statement containing phrase "belongs on":

"This question belongs on another site in the Stack Exchange network."

I didn't find "belong on" on any dictionary, even its usage percentage is zero as compared to "belong to" on Google ngram site.

Is it still fine to use preposition "on" instead of "to" to refer anyone's relation with others?

Solution 1:

Both prepositions are fine, but there is a difference in meaning.

This question belongs on another site in the Stack Exchange network.

The question should be moved to the other site.

This sense of belong is "1. suitable, appropriate, or advantageous."

This question belongs to another site in the Stack Exchange network.

The question already is on the other site.

This sense of belong is "2. the property of a person or thing."

Solution 2:

The verb 'belong' as used here means 'to be in the right place or a suitable place'. You can follow it with many prepositions of place or location such as in, on, under, over, etc. That dishonest man belongs in prison. That picture belongs above the fireplace.

Dirty boots do not belong on the table, now do they?

Belong (Cambridge)