fix mastodon-width in Greasemonkey
fix mastodon-width in Greasemonkey

Tampermonkey is fine with @run-at document-start, but Greasemonkey
isn't.

If I remove @run-at, Tampermonkey then flashes an unstyled page, which
is ugly.

Tampermonkey supports document-body, which avoids the flash, and
Greasemonkey ignores it, so this seems a good workaround.

jennings/userscripts