Suggestions for vertbars

The following packages have something in common with the package vertbars. The packages are ordered in decreasing similarity.

Package changes: Manual change markup
Package todonotes: Marking things to do in a LaTeX document
Package prelim2e: Allows the marking of preliminary versions of a document
Package luatodonotes: Add editing annotations in a LuaLaTeX document
Package comment: Selectively include/exclude portions of text
Package draftwatermark: Put a grey textual watermark on document pages
Package optional: Facilitate optional printing of parts of a document
Package changebar: Generate changebars in LaTeX documents
Package fixme: Collaborative annotation tool for LaTeX
Package nameauth: Name authority mechanism for consistency in body text and index
Package xechangebar: An extension of package changebar that can be used with XeLaTeX
Package attachfile2: Attach files into PDF
Package attachfile: Attach arbitrary files to a PDF document
Package pdfmarginpar: Generate marginpar-equivalent PDF annotations
Package repltext: Control how text gets copied from a PDF file
Package hypgotoe: Links to embedded files
Package pst-pdf: Make PDF versions of graphics by processing between runs
Package ed: Editorial Notes for LaTeX documents
Package draftmark: Put draft marks on selected pages
Package errata: Error markup for LaTeX documents
Package minorrevision: Quote and refer to a manuscript for minor revisions
Package vrsion: Add version number to a DVI file
Package draftcopy: Identify draft copies
Package extract: Write selected parts of a document to a separate file
Package caption2: Superseded version of the caption package
Package cuted: Mixing onecolumn and twocolumn modes
Package newproof: Make commands to define proofs
Package resizegather: Automatically resize overly large equations
Package exam: Package for typesetting exam scripts
Package fvextra: Extensions and patches for fancyvrb
Package llncs: Document class and bibliography style for Lecture Notes in Computer Science (LNCS)