Drops \usepackage{xurl} (or \RequirePackage{xurl} in the shared ac-paper-layout.sty) right after hyperref in every paper that loads hyperref. Without it, two-column layouts let URLs overrun the right margin in citations and footnotes — a long-standing complaint across the dossier set. xurl breaks URLs at any character; hyperref alone breaks only at hyphens (and only with the [hyphens] option). Verified by recompiling arxiv-recurse with xelatex — log shows xurl loading cleanly, PDF generates, residual overfull-hbox warnings are unrelated paragraph/ table issues. 124 .tex + 14 .sty (canonical + 13 per-paper copies) updated. Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>