quequotion [1] filed a deletion request for epiphany-pantheon [2]:
Redundant, as GNOME opted to code their browser detect when running in
Pantheon and behave accordingly.
Rather have this gone than port the "double click for new tab" (which
is more annoying than useful anyway) patch to 3.36.
[1] https://aur.archlinux.org/account/quequotion/
[2] https://aur.archlinux.org/pkgbase/epiphany-pantheon/