# Hover Zoom+: the malware-cleaned fork that enlarges browser images on hover > Hover Zoom+ is a browser extension for Chrome, Firefox and Edge that enlarges images and videos to full size on mouse hover. It replaced the original HoverZoom after that extension was deleted from stores for bundling spyware. **extesy/hoverzoom** — Google Chrome extension for zooming images on mouse hover - Repository: https://github.com/extesy/hoverzoom - Website: https://chrome.google.com/webstore/detail/hover-zoom%20/pccckmaobkjjboncdfnnofkonhgpceea - Stars: 2,060 · Forks: 222 - Language: JavaScript - License: MIT - Published: 2026-10-11 · Updated: 2026-10-11 · Language: en - Canonical page: https://hysenlabs.com/projects/extesy-hoverzoom ## The original HoverZoom was deleted from the Chrome Web Store after a malware infection Why this extension exists matters as much as what it does. The original HoverZoom offered the same hover-to-zoom behavior but was removed from the Chrome Web Store after malware was discovered inside it. Hover Zoom+ grew from that removal. According to the README: "This is an open-source version of the original HoverZoom extension, which was overrun by malware and deleted from the store. In this version all spyware has been removed, many bugs were fixed and new features were added." For a browser extension, which by design can observe the pages a user visits, privacy is the claim that deserves the most scrutiny. The README states it collects no user data whatsoever. Author Oleg Anashkin has published a record of all acquisition offers received over the last few years in the repository's discussion thread at discussions/670. That discussion is linked directly in the README alongside the commitment: "This extension will never be sold out, and it will never compromise users' privacy." A public list of rejected offers is documented evidence rather than a blanket assurance. Whether the commitment holds depends on the project remaining under its current author. Anyone migrating from the original HoverZoom should uninstall that extension before adding this one, since both share similar names across some stores. The source code is available under the MIT licence at the repository root. ## Hover events trigger a full-size image fetch that scales within the viewport When a mouse cursor passes over a supported image, the extension fetches the full-size version and displays it enlarged while keeping the result within the browser window's edges. The README states: "Hover your mouse over any image on the supported websites and the extension will automatically enlarge the image to its full size, making sure that it still fits into the browser window." Videos are supported alongside images. No permanent UI element is injected into pages. On hover, the extension identifies the full-size source URL for that image using a site-specific plugin file, fetches that resource, and overlays the result. When a page serves images from a CDN with dimension parameters embedded in the URL, the relevant plugin handles stripping or replacing those parameters to reach the original file. Zoom ends when the mouse moves away. No keyboard shortcut to pin the overlay open is documented in the README, and no download feature appears. Saving the full-size image requires the browser's own right-click menu or a separate download tool. Display is the only purpose the extension covers. ## Site support lives in a plugins/ directory, not in a generic image detector When the README mentions supported websites, it links to the plugins/ directory: "Hover your mouse over any image on the supported websites." That phrase is the key constraint. Hover Zoom+ does not work on every page. It works only on pages where a matching plugin file exists in that directory. Every supported site requires its own plugin. When a site changes its image URL patterns or HTML structure, the matching plugin breaks until someone updates it. The README acknowledges this: "Sometimes sites change design, and when it happens, the extension needs to be updated. Please report any issues with zooming not working by filing an issue on https://github.com/extesy/hoverzoom/issues page." Adding a new site means writing a plugin file that follows the format of the existing ones in plugins/, then either maintaining a private fork or contributing upstream. No tutorial for writing a new plugin appears in the README, so understanding the required format means reading the existing files in that directory. The README names Facebook and Amazon as examples of supported sites, which gives a sense of the target profile: large consumer platforms with predictable image URL patterns. One aspect is easy to overlook: nothing in the extension's interface signals whether a given image has an active plugin or not. A hover that produces no overlay on a page without a plugin looks identical to a hover on a site whose plugin broke after a design update. Both failures are silent, and only checking the issue tracker reveals whether a particular site's plugin is known to be broken. ## Chrome and Firefox use different store names for the same extension 3 store listings cover the 3 supported browsers. Chrome users install from the Chrome Web Store using the link in the README. Firefox users find the extension at addons.mozilla.org/en-US/firefox/addon/hover-zoom-plus/ under the name hover-zoom-plus. Edge users install from microsoftedge.microsoft.com/addons under hover-zoom. Using hover-zoom or hoverzoom as a search term on Firefox returns nothing useful in the Firefox Add-ons catalog, because the Firefox listing uses the hover-zoom-plus suffix. This is practical friction for users who hear about the extension and search by name on Firefox without knowing the platform-specific variant. For end users, a store install is the only documented path. No zip download link, no sideload instructions, and no steps for loading an unpacked extension in developer mode appear in the README. Building from source is a separate process intended for contributors, not an alternative install route for ordinary users. ## The build script produces hoverzoom.zip; web-ext starts the Firefox development instance For developers who want to modify the extension or run a local build, the package.json scripts section defines 2 entry points. One bundles the distributable by zipping 8 source directories and the manifest: _locales, css, fonts, html, images, js, plugins and manifest.json, producing hoverzoom.zip. The second entry starts a Firefox development session: ```bash web-ext run --source-dir ./ ``` This command, defined in the firefox script of package.json, starts a Firefox instance with the extension loaded from the current directory. The 4 devDependencies in package.json are web-ext, eslint, eslint-config-airbnb-base and eslint-plugin-import. A discrepancy in package.json is worth noting for any tooling that reads it: the version field reads "1.0.0" while the project's GitHub tag history shows 1.1.16, because the npm version field is unused and the extension's actual version number lives in manifest.json. Any tooling that reads the npm version field will return "1.0.0" regardless of the code present. ## Zoom stops working silently when a site redesigns before a plugin update ships Plugin dependency is the main limitation for general use. On any site not represented in the plugins/ directory, hovering produces no effect. For someone expecting the extension to work everywhere, the gap appears without any explanation or error state in the browser's UI. When a supported site changes its image URLs or markup, there is no documented workaround until the plugin is updated. Filing an issue at the GitHub issue tracker, as the README instructs, is the only path. No fallback behavior activates when the specific plugin fails, and no notification appears in the browser to signal that zoom has stopped working for a particular site. The period between a site's redesign and the corresponding plugin update is a dead interval with no in-browser signal. A second constraint concerns scope. Hover Zoom+ depends on a human moving a mouse cursor inside a browser tab. Any use case requiring full-size image extraction without browser interaction, processing images at scale, or operating headlessly is outside what this project covers. The README makes no claims in that direction. ## Twenty-four locale folders ship with the extension; Crowdin handles translation contributions The repository root holds 23 entries at the top level. Among them, Crowdin's configuration file crowdin.yml sits alongside the 24 locale folders bundled with the extension: ar, bg, de, en, es, fa, fr, hi, hr, hu, id, it, ja, ko, nl, no, pl, pt_BR, pt_PT, ru, sv, th, tr and zh_CN. Those cover Arabic, Bulgarian, German, English, Spanish, Farsi, French, Hindi, Croatian, Hungarian, Indonesian, Italian, Japanese, Korean, Dutch, Norwegian, Polish, Portuguese for Brazil and Portugal, Russian, Swedish, Thai, Turkish and Simplified Chinese. Translation contributions do not arrive through GitHub pull requests. The README links to crowdin.com/project/hoverzoom and asks contributors to help with localisation there. Changes to the _locales directory are merged into the repository separately from code changes. At the repository root, the top-level entries include CONTRIBUTING.md and an AGENTS.md file alongside the extension's build scripts. AGENTS.md is an unusual addition for a browser extension project and is not described in the README. Its purpose is not explained anywhere in the top-level listing. ## Conclusion Hover Zoom+ fits anyone who browses image-heavy sites regularly in Chrome, Firefox or Edge and wants the full-size version of every image one hover away. It is the wrong choice for developers who need hover zoom to work reliably on internal or uncommon sites that have no plugin in the repository. The risk of an undetected zoom failure is real: there is no indicator in the extension's interface when a plugin stops matching after a site redesign. Before relying on it, verify that a plugin for your primary sites exists in the plugins/ directory at github.com/extesy/hoverzoom, then check the issue tracker for open reports against those specific sites. ## FAQ ### What is Hover Zoom+? Hover Zoom+ is a browser extension for Chrome, Firefox and Edge that enlarges images and videos to full size when you move the mouse cursor over them. It is an open-source replacement for the original HoverZoom extension, which was deleted from stores after malware was found in it. ### How do I install Hover Zoom+? Install from the Chrome Web Store for Chrome, from addons.mozilla.org/en-US/firefox/addon/hover-zoom-plus/ for Firefox, or from microsoftedge.microsoft.com/addons for Edge. No sideload or command-line install path is documented in the README. ### Why does Hover Zoom+ not work on all websites? The extension only zooms images on sites that have a matching plugin file in the plugins/ directory of the repository. Sites without a plugin are not supported, and supported sites can stop working when they redesign before a plugin update ships. ### How is Hover Zoom+ different from the original HoverZoom? According to the README, the original HoverZoom was deleted from the Chrome Web Store after malware was found in it. Hover Zoom+ removed the spyware, fixed bugs and added new features. The README states the extension collects no user data. ### How do I add support for a new site to Hover Zoom+? Adding support requires writing a plugin file that follows the format of the existing files in the plugins/ directory, then contributing it upstream or maintaining a private fork. No tutorial for writing plugins appears in the README. ## Sources - [extesy/hoverzoom on GitHub](https://github.com/extesy/hoverzoom) - [License: MIT](https://github.com/extesy/hoverzoom/blob/master/LICENSE) - [Project website](https://chrome.google.com/webstore/detail/hover-zoom%20/pccckmaobkjjboncdfnnofkonhgpceea) - [README](https://github.com/extesy/hoverzoom/blob/master/README.md) - [Releases](https://github.com/extesy/hoverzoom/releases) --- Hysen Labs editorial analysis, written from the project's own repository and release notes. Cite the canonical page: https://hysenlabs.com/projects/extesy-hoverzoom