gnu: Add texlive-longfbox.

* gnu/packages/tex.scm (texlive-longfbox): New variable.

gnu/packages/tex.scm

@@ -87495,6 +87495,27 @@ (define-public texlive-logpap
 linear-linear graph paper with LaTeX.")
     (license license:lppl)))
 
+(define-public texlive-longfbox
+  (package
+    (name "texlive-longfbox")
+    (version (number->string %texlive-revision))
+    (source (texlive-origin
+             name version
+             (list "doc/latex/longfbox/" "tex/latex/longfbox/")
+             (base32
+              "1yqjn1xmn10g5rhd1prbndzxyccy3z8piab5aribzgl5kw466zyn")))
+    (outputs '("out" "doc"))
+    (build-system texlive-build-system)
+    (home-page "https://ctan.org/pkg/longfbox")
+    (synopsis
+     "Draw framed boxes with standard CSS attributes that can break over multiple
+pages")
+    (description
+     "The @code{longfbox} package provides framed boxes that can be customized
+using standard CSS attributes.  It was written to support precise rendering of
+Madoko documents in LaTeX.")
+    (license license:lppl1.3+)))
+
 ;;;
 ;;; Avoid adding new packages to the end of this file. To reduce the chances
 ;;; of a merge conflict, place them above by existing packages with similar