CONTRIBUTING.md has said 'do not submit PRs directly to main' since it
was written, and says 'when in doubt, target dev'. Twenty-one open PRs
were still sitting on main, some of them a year old, because GitHub
preselects the default branch in the PR form and nobody reads a
CONTRIBUTING link while filling one in.
The default branch stays main, so the reminder has to be at the moment
of creation instead: the composer comment, which is on screen right
below the base selector, and a checklist item so a reviewer can see it
was skipped. All twenty-one have been retargeted.
Bingxi Zhao (Frank)
a7df6ca65d