Double-clicking on a text object in the graphics pane selects the text (it will be highlighted in blue). If you start typing while the entire text is highlighted in blue, the text will be overwritten. Once the text is selected, clicking anywhere within the text places the cursor at that location.
You can also use the Home, End, Backspace and arrow keys to move the cursor in the selected text.
A single click on a text object selects the object, but does not select the text itself. Eight "handles" will be visible, defining the limits of the textbox (one at each corner, and one on each side).
By default, word-wrap is on, so the text will wrap around given a specified width. As you type, the textbox will automatically expand downward.
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