In this example, the left sidebar is sticky, and so are the headers of the address book entries below.
Both are initialised with using the command, but they have evry different styling and apparent behaviors.
aaaaaaaaaaaaa
aaaaaaaaaaaaa
aaaaaaaaaaaaa
aaaaaaaaaaaaa
bbbbbbbbbbbbb
bbbbbbbbbbbbb
bbbbbbbbbbbbb
bbbbbbbbbbbbb
ccccccccccccc
ccccccccccccc
ccccccccccccc
ccccccccccccc