_Added in 2.7_

*<notextile>on <level>:MSCROLL:<*#?=!@>:<commands></notextile>*

Triggers when a user scrolls the message buffer in a window.

_See also [[$mscroll.pos]], [[$mscroll.max]]._

*Parameters*

<level> - The level for the event to trigger.
<*#?=!@> - The [[Matchtarget]] to listen to.
<commands> - The commands to be performed when the event listener's criteria is met.

*Example*

<pre>
on *:mscroll:#:{
  if ($mscroll.pos == 1) {
    echo -sg scrollbar for $active is at top
  }
  else if ($mscroll.pos == $mscroll.max) {
    echo -sg scrollbar for $active is at bottom
  }
}
</pre>