Set Duration for Elements
Having added apply all your videos, images and elements to Timeline, you have to click one element to select it.
Next, let’s enter the setting mode.
Now you can see where to set the duration for your elements.
You can apply your change to all elements by clicking the button “Apply to all”.
Make sure you have clicked “Ok” to save your changes before leaving.
Besides, you can choose to lengthen or shorten your element by dragging it.