urxvt built-in clipboard "autocopy" feature?

[drzraf]

I see that the clipboard extension is said "obsolete".
Still, urxvt, natively can either:

• store the selection in PRIMARY
• store the selection in CLIPBOARD (if selection-to-clipboard is enabled)

But, to my knowledge, and contrary to clipboard + autocopy, it's can't do both (= sync'ing clipboard).
I confirmed and no native replacement exist, why is the "clipboard" extension "obsolete"?

[nesaro]

The https://github.com/muennich/urxvt-perls/blob/master/deprecated/README.md says:

Since version 9.20 rxvt-unicode natively supports copying to and pasting from
the CLIPBOARD buffer with the `Ctrl-Meta-c` and `Ctrl-Meta-v` key bindings. The
`clipboard.autocopy` setting is provided by the `selection-to-clipboard`
extension shipped with rxvt-unicode.