Sample Text Content for Testing
This is the first paragraph of test content. It contains multiple lines of text that you can use to test selection extension functionality. Try selecting part of this text and then extending the selection to different points on the page.
Here is a second paragraph with different content. Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation.
The third paragraph contains even more text for testing purposes. You should be able to select text in any of these paragraphs and then extend the selection to points in other paragraphs or different lines within the same paragraph.