Question: how to select execution group without having to scroll to copy its content?

Another worksheet dilemma  I am having with Maple.

I have number of "execution groups", like this, I created using CTRL-J

Now I wanted to put these in a section, so it becomes like this: (I had to make new worksheet now)

Since I did not know how put existing groups inside a new section I wanted to create (the section always comes at different level that does not include the groups), I thought I can create the section first, then go copy the groups and paste them to the new section.

The problem is how does one actually select multiple execution groups for the purpose of copying them?  The obvious way is to use the mouse, and select all groups with the mouse.

Well, this a big problem, since my groups are so large, I can spend 5-10 minutes scrolling down, very slowly to select them. my hand gets tired and I get tired doing this. I also one time got an error from Maple, saying selection too large, and something about rtf memory error or something. This is after wasting 10 minutes scrolling down carefully to select over 10,000 lines that is one large list.

In Mathematica, I can simply select a cell, no matter how large (an execution group in Maple talk) by just clicking on the edge of the cell.  I can select multiple cells the same way (hold, click on the edge of all). Very easy. I do not have to scroll down to select the content as I do with Maple

But here, with Maple, I put the mouse of the left edge, and can't select the group. Nothing happens. So I have to actually scroll down. I do not see the point of having a left [ edge to a group if one can't use it to select the group?

So my question is: How to select one or more execution groups without scrolling the mouse over all the content?