you need to be more accurate than than.
one way for showing playtime and remove it is either in menu, or by
adding a text with the js call with srd hudmaker, and bound it to a switch in
a common event, probably with "button common events" plugin to toggle
ON and OFF with a press of a button.
else explain a bit more on the situation where and why the playtime need to show
and when not (delete teh playtime), so we can give a better solution to your problem.
while this is plugin support, if it is a plugin, which plugin are we talking about?
so you didn't actually state what you wanted or how you wanted to achieve it - only what the end result should be. Hence the value of taking the time to explain what you want, rather than assume the title says it all.
There is no playtime window that can just be displayed or hidden, so you will need a plugin.