Add alt text

quarto-formats.qmd

@@ -139,6 +139,8 @@ If you're viewing this page on the web, you can drag the map around, zoom in and
 You obviously can't do that in a book, so Quarto automatically inserts a static screenshot for you.
 
 ```{r}
+#| fig-alt: Leaflet map of Maungawhau / Mount Eden.
+
 library(leaflet)
 leaflet() |>
   setView(174.764, -36.877, zoom = 16) |>