This is a limitation on github urls, seems about 8195 (including https://github.com)
I think maybe we can copy the body to clipboard and open a url like this
https://github.com/sindresorhus/np/releases/new?body=<!--%20paste%20your%20release%20nodes%20here%20-->
Maybe new-github-release-url should also throw an error.
Can you submit a bug report to GitHub? They should really support longer URLs than that.
I don't think that solves the problem, even if github supports longer urls, the url length can still reach the browser's url length limits. In chrome about 2MB
Yes, but you're much less likely to hit the browser URL limit. So it's still worth sending a bug report.
OK, I'll let you know when they reply.
That means about a million characters. If your release notes are that long, this is the least of your problems 馃槤
Hmm, something similar just happened to me, but instead of opening this 414 Request-URI Too Large error, nothing was opened at all... The release had 110 commits since the previous one, so I wonder if that enough blew the size up.
By the way, of those, almost 100 were commits by Renovate bot, which I redacted from the release notes while doing it manually, since np didn't work. I was expecting to get the generated release and just delete those commits from it.

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That means about a million characters. If your release notes are that long, this is the least of your problems 馃槤