Skip to main content
ScholarBits

Hover-Legend Viewer

Guide

How to enable hover-legend overlays in PDF readers — setup guide

All PDF Reading
What is Hover-Legend?

Hover-Legend is a technique where hovering your cursor over a figure in a PDF reveals a floating overlay showing the figure legend — so you don't have to scroll back and forth between the figure and its caption.

This feature requires a browser extension or a specialised PDF reader. It cannot be implemented as a web-only tool.

Option 1 — Adobe Acrobat
Desktop
  1. Open the PDF in Adobe Acrobat Pro DC.
  2. Go to View → Page Display → Single Page Continuous.
  3. Use Edit → Find to navigate to the figure caption, then right-click → Create Link to manually link captions to figure locations.
  4. Save the annotated PDF for reuse.

Note: Acrobat does not provide hover overlays natively — links are the closest equivalent.

Option 2 — Zotero + ZotFile
Desktop
  1. Install Zotero 6 and the ZotFile plugin.
  2. Open the PDF in Zotero's built-in reader.
  3. Highlight a figure, right-click → Add Note. The note appears in the right panel and can contain the legend text.
  4. Use the note sidebar to view the legend without leaving your reading position.
Option 3 — Chrome/Firefox Extension
Browser
  1. Install the ScholarlyPDF or Lean Libraryextension for your browser.
  2. Open a PDF in the browser. Some extensions automatically detect figures and attach floating legend overlays.
  3. Hover over a figure element to trigger the overlay.

Extension availability varies. Check the respective extension stores for the latest compatible versions.

More in PDF Reading

View all →

Note-to-Markdown Snapper

Formats raw PDF annotations into atomic Markdown notes with backlinks.

ArXiv Sync Monitor

Checks ArXiv preprint IDs against the API to detect published DOIs.

Supplemental Fetcher

Fetches supplementary material links for a DOI via Unpaywall and CrossRef.