Hello Wutthipong,

Currently it is not possible to add captions on images that appears on a thumbnail block. You can however add a column block and insert multiple image blocks with captions if you need to.

Hi Mark,

OK I see, and I hope thumbnail and gallery block can add caption. Thank you.

You are most welcome.

As a gentle reminder, kindly start a new thread if you have any other issue in the future so it will be easier for us to manage your inquiry. I will lock and mark this thread as resolved.