RSLogix 5000 How to duplicate tags?

I have two copies of RSLogix 5000 open looking at two seperate Control Logix processors.

Is there any way to copy a tag from one CLx and paste it into the other one?

I can't use the export/import utility because I have to make these changes online with the PLC in Run mode.

It's no problem to copy and paste rungs of ladder, but I don't know how to duplicate the tags.

I'm using RSLogix 5000 Rev 15.00

Go to the tag list on the source RSLogix Project, highlight the row(s) you want, select 'Edit | Copy'.
Go to the Tag List (Edit Mode) on the target Project, click on the blank row at the bottom, and select 'Edit | Paste' (or CTRL-V)

I was able to highlight the row in the source program and was able to select 'Edit | Copy'. However when I went to the destination program and selected the bottom blank row the 'Edit | Paste' was greyed out. If I selected just the tag name in the blank at the bottom it would paste what appeared to be all the tag info, but into the name field which is invalid.

For the destination Controller tags display i'm using the Edit Tags tab at the bottom.

I also tried dragging and dropping between the two copies of RSLogix 5000. When I dragged over the other copy of RSLogix 5000 the mouse pointer turned into a circle with a slash through it.

In further testing, I discovered that I can drag and drop or copy and paste tags if the destination PLC is offline, but not if it's online.

This is kind of weird because I can add and delete tags online with no problem. The tags that I'm trying to copy and paste are DINTs so it's nothing exotic.