Replace text

Hi there
Could you please make it that when I click into text field area that my input text for description etc replaced the text in the box without having to select all and delete – hope that makes some sense- see here: http://screencast-o-matic.com/watch/cDhqjUiVtw

https://ww.wp.xz.cn/plugins/ultimate-shortcodes-addon-for-king-composer/