the new freeze feature is good, thanks, however it is not easy to set the duration of the freezed frame manually on the clip property panel, in duration box.
is this by design, or it is a bug?
By design. You cannot edit the duration of any timeline clip in Properties. To change the duration of a freeze frame you drag the right edge of the clip just like any clip on the timeline. You will usually find it useful to turn on Ripple before doing so.