Was out of Curiosity?

out of curiosity simply means that you are interested in knowing something for no other reason except that you just want to know it.

Can I ask something out of curiosity?

People can ask a question out of curiosity. This means they are asking a question they are curious about (something they want to know about). ... People can look at something out of curiosity. This means that they want to know about something by looking at it.

What does out of mere curiosity means?

to decide to stop quarreling.