This becomes helpful for some children and elders to recognize instantly which sites are not secure to communicate on or share information on if they are tagged in red color. After Chrome 68 update it’s already marking all non-HTTPS sites as Not Secure but in Grey color which may not look much suspicious to children or elders or non-tech-savvy users so why not mark them in Red color. Chrome has this very option in back-end settings. Follow below mentioned steps to do it.
How To Make Chrome mark All Non-HTTPS Sites Not Secure In Red Color
Setting it up
or use this direct link