well, filemaker isn't a web browser. But I agree that would be a nice feature, although I rarely nest scripts so I rarely am editing more than one at a time.
Sounds like a feature request:
I am not sure if this helps or not, but when I closed all my scripts so none were open. Then double click on the scripts you want to display, in order. They will show up, left to right.
I think that may deal with your question. Not exactly like rearranging them in a web browser but pretty easy to do.
So, it would be nice if the scripts list can show "last modified" and sort with it
Tab can be moved to new window, so I thought reverse it will be workaround for rearrange, but there is no menu for move window to tab...
I use a comment at the beginning of each script to (manually) track modification date of scripts. I don't think I've ever wanted to sort by it, but it'd sure be great if it could be tracked/displayed automatically.