How to insert a task on the Timeline?



I have a long list of tasks lined up on Timeline and I sometimes want to insert a new task in the near future and put the rest of the tasks off.

I wish I could do it just by putting a task on my desired position and the the other tasks slip automatically. However, what I do now is to select all the tasks and drag them to create new spece and put a new task there.

I created a video of what I do now.

Since my real timeline is a lot larger, this is a huge pain for me.
Is there any good tip to do this more efficiently?