How can I add element to iframe without erasing previous one?

Question

I just want to add new element but method I am using erase the previous one and I don't want to use textarea..
https://code.sololearn.com/WN2tSDzwcKYW/?ref=app

Answer 1

https://code.sololearn.com/W9Fpgd0uac57/?ref=app

Answer 2

Thanks to both of you

Answer 3

this will help you

Answer 4

welcome friend

Answer 5

Ok now help me with another problem how can I change style of iframe

Answer 6

I would be happy if you share me your code