update;

docs/introduction-to-qgis.html

@@ -853,6 +853,14 @@ <h2>1.3 Labelling</h2>
 <li>Click on the label again to start moving it. Drag your mouse to the
 new label location and click again to move the label.</li>
 </ol>
+<blockquote>
+<p>Tip: If a label disappears after moving it, it means that it has been
+placed at a position that cannot be displayed on the map without
+colliding with other labels. You can see the unplaced labels by clicking
+the <em>Toggle Display of Unplaced Labels</em> button on the <em>Label
+Toolbar</em>. Once the label is shown, you can move it to another spot
+where it can be displayed.</p>
+</blockquote>
 <p><img src="images/introduction_to_qgis/earthquakes_part3_14.png" width="75%" style="display: block; margin: auto;" /></p>
 <ol start="15" style="list-style-type: decimal">
 <li>Similarly, move other labels to appropriate locations. Once you are

introduction-to-qgis.Rmd

@@ -441,6 +441,8 @@ knitr::include_graphics('images/introduction_to_qgis/earthquakes_part3_13.png')
 
 14. Click on the label again to start moving it. Drag your mouse to the new label location and click again to move the label.
 
+> Tip: If a label disappears after moving it, it means that it has been placed at a position that cannot be displayed on the map without colliding with other labels. You can see the unplaced labels by clicking the *Toggle Display of Unplaced Labels* button on the *Label Toolbar*. Once the label is shown, you can move it to another spot where it can be displayed.
+
 ```{r echo=FALSE, fig.align='center', out.width='75%'}
 knitr::include_graphics('images/introduction_to_qgis/earthquakes_part3_14.png')
 ```