Some Markdown Not working on steemit need to be added

Using markdown on steemit have been on of the best thing for some of steemit users because most find it easy in using markdown to format post thereby making it more presentable.

Recently I discover there are some post format markdown which are not working, let me say isn't yet inserted.
Markdown like

underline

I found it hard to underline words on steemit because the underline markdown is not activated ( < u >)... (</ u>)

insert text markdown

This is also not activated ( < ins > )... (</ ins >)

I hope this can be look into and fixed