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Vertical Tab Groups
Horizontal Tab Groups
You can move a tab from one tab group to another tab group by dragging and dropping the tab. You can also create additional tab groups by repeating the process that creating the initial tab group. However, all tab groups must be of the same type; you cannot mix horizontal and vertical tab groups. If you close or remove the last tab in a tab group, Template Editor will eliminate the tab group.
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To create a split window grab the splitter handle at the top of the vertical or horizontal scroll bar (highlighted in green in the image below) with the mouse and drag it downwards. The result will be a single window with two panes, both of which open on the same file:
You can scroll and edit in the two panes of a split window independently. Because the two panes are both views into the same underlying file, any changes in one pane are immediately reflected in the other pane.