https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91847
--- Comment #2 from Barry Revzin <barry.revzin at gmail dot com> --- In the Prague meeting, this paper (https://brevzin.github.io/cpp_proposals/2095_lambda_pack_cwg/p2095r0.html) was adopted into what will become the C++20 standard, which moves the & in the grammar to the left side of the ellipses. So now I can say officially, [&...us=ts]{} is the correct spelling.
