There is already a gist available, just making it somewhat easy to use as Docker container or vagrant config, so it could be useful to others

Utilities to extract and merge PDF annotations

PDF format annotation and labeling support for Label Studio

Tiny tool help creating PDF links in Adobe Illustrator.

Fork of Moodle/editpdf, with custom options

A JavaScript library for annotation

Flare is a LaTeX package and an extension to \includegraphics copying PDF annotations.

Search comments and highlights annotations in PDF documents.

A software for extracting pdf annotations.

Full-featured PDF viewer with enhancements especially for academic papers

A React component for annotating PDF, powered by PDF.js and RecogitoJS

Display PDFs with a pointer, make quick annotations (that automatically disappear), and zoom them

beCPG Artworks Addon

An easy-to-use Python library for annotating, manipulating and processing PDF files

Knowtate is a sophisticated platform designed to elevate your academic research experience. Seamlessly blend reading, note-taking with markdown, and knowledge management into one intuitive interface, allowing you to effortlessly track your insights and ideas as you delve into scholarly literature.

Annotation layer for pdf.js

An annotation extension based on the PDF.js viewer. Supporting the editing of existing PDF file annotations, posting comments, replying, submitting annotation data, and loading for further editing.

Simple "digitial paper" for note taking and PDF annotation. Heavily inspired by Xournal.

Theses-Checker is a tool for students and teachers alike to check theses for frequent typographical errors. (This program is a part of a bachelor's thesis.)