Image enlargement extension Imagus for Firefox

Martin Brinkmann
Nov 22, 2014
Firefox, Firefox add-ons

I reviewed Imagus back in 2013 when the then popular extension Hoverzoom caused controversy in regards to scripts it ran that were not in any way related to enlarging images on the Internet.

Imagus came to same fame and many call it the best Chrome extension of its kind. The author of the extension ported it over to Firefox recently and it has been available for the web browser for a couple of months.

The add-on works similar to its Chrome sibling. You move the mouse cursor over an image on a website and it will display a larger version of it if provided or zoom the original image instead if that is not the case.

Imagus ships with supports for a large number of popular sites such as eBay, Reddit, Imgur, Wikipedia, DeviantArt, many Google services, Facebook or Twitter to name a few. All in all, it offers more than 200 default rules that ensure that it works on popular websites and services right out of the bat without any form of configuration.

While designed with enlarging images in mind, it works with other types of media such as video or audio contents as well provided that there is a rule for it available.

As far as rules are concerned, you can look them all up in the options under sieve and create your own ones as well. The syntax uses regular expressions and it may make sense to study some of the existing rules the extension ships with to understand how to create your own.

There is also an option to define rules that block or allow specific sites or part of sites. This can be useful if you want the extension to work on a particular part of a site or block it from working on another. This uses regular expressions as well.

Besides that, there are also lots of options and preferences to play with. It is possible to add a hotkey to the functionality so that media only gets enlarged when you hit the key. This can be useful if you need the functionality at times but not all the time since it will enlarge images that you come across when you hover over them and a rule exists otherwise.

Other features include image preloading to speed things up, showing or hiding captions, defining where the image popup appears on the screen, or blocking hovered links from appearing in the browsing history.

Imagus supports a large list of shortcuts that come in handy as well. From default shortcuts such as Ctrl-s to save contents right away over +/- to zoom in or out to album and media specific shortcuts to jump to the next or previous image or pause playback.

Closing Words

Imagus is a useful browser extension that is now available for Chrome and Firefox. It is quite powerful thanks to its rules system and while it requires knowledge of regular expressions for customization purposes, it works quite well in its default state on many popular sites.

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  1. anonymous said on November 23, 2014 at 6:32 am

    I can’t get it working. I think its because of the NoScript add on. Does anyone know how to make Imagus work with NoScript?

    1. Martin Brinkmann said on November 23, 2014 at 9:02 am

      It depends. On some sites, it does not require any configuration. If you check Imgur for example, you should see the larger image versions right away even if you don’t allow anything on the site.

  2. Doc said on November 22, 2014 at 11:31 pm

    I much prefer Image Zoom (for Firefox), which works on *all* images out-of-the-box, although you have to right-click and roll the scroll wheel (or right-click and pick a preset zoom). Only problem is that some CSS prevents the images from zooming (presumably the CSS max-width setting); in this case, I view the image in a new tab to zoom in.

    1. Chains The Bounty Hunter said on November 23, 2014 at 9:00 pm

      Used this for years, gets the job done for roughly 95% of what I need it for.

  3. Blue said on November 22, 2014 at 11:21 pm

    ***Side Note*** As of current the version of Hover Zoom is up to 5.5 and there is no script injection anymore since 5.2 as too many people complained. The reason why I like Hover Zoom is not really for the zoom capability, but for the fact it has added the ability to save the image with a single key tap (default S which in Facebook should be changed to another letter because it sometimes launches a FB shortcut to share a page) especially useful for pages that disable R clicking images to save.

    Image save is also available for this Imagus, but it is now a two key operation and can no longer be a custom key set (CTRL + S).

  4. xtremezz said on November 22, 2014 at 1:00 pm

    Currently using Thumbnail Zoom Plus, which has served me well so far. Has anyone compared these two?

    1. Pants said on November 22, 2014 at 1:51 pm

      Also been using TZP (latest beta) for .. years. I even emailed him with the rules to enlarge images from itunes and other sites where the link is not available, just needs some tweaking – and he added them in (well, most of them). He’s very approachable (you’ll be amazed at how many developers are happy to listen and implement ideas – I’ve talked to dozens and they all oblige).

      eg – itunes thumbnails for music
      change 170×170 to 600×600 (and also 1500×1500 used to work) to get the large image

      But I suspect that Imagus might be more powerful in that you can create your own rules and filter for sections of domains etc.

  5. Lecquio said on November 22, 2014 at 12:49 pm

    Imagus is a must have extension.
    I use it in Opera since many years ago and I didn’t know it has a firefox version.

  6. John said on November 22, 2014 at 11:44 am

    Hi Martin,

    do you have any info regarding the reputation of this userscript?

    Is it trustworthy? I’ve been using it for a good while and it’s fantastic. But a script, still.

    1. infosec said on November 23, 2014 at 8:09 pm

      There is no good way to scan Javascript for malicious code. You can’t do it. The problem is that there are too many ways a malicious/rogue developer can hide malicious stuff in their code, and you’ll never be able to detect it all.

    2. Martin Brinkmann said on November 22, 2014 at 11:52 am

      John I don’t know the script but it looks quite popular. Cannot really say anything about trust though, sorry. Update: Have reviewed it but could not remember:

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