Editor.on('component:update:content', model => { }}) not work in some cause

if the user remove all text from a element and click some where else . then again try to select empty element he is not able to select it again because it is hide and i dont know where it goes. So for this issue I am using this code this code set a space in text if user remove all text from a element . By doing this these is no empty element so i does not hide . and again we can select it . if the user remove text character one by one it works fine . But now issue is that if a user select a text by CTRL + A and remove by BACKSPACE . At this time this above code not work . Can anyone help me .