FF AdBlock add-on blocking local images

I received an email last night from a colleague regarding his recent visit to the Fubra site using the Firefox web browser. In his email Matt Wardy pointed out that he could not see the central image on the homepage relating to advertising.

Fubra Site - Adblock image issue

Whilst digging around for a reason he found that there was an inline style of “display: none;” applied to the image although no inline style was visible in the source code, which asked the question of where was it coming from?

As with many development and layout issues in Firefox they often come back to one of the many extensions or add-ons that you have installed – for example wondering why JavaScript isn’t working and then realising that it’s simply because you had disabled it earlier on to ensure your site will work without it enabled :S.

In this case it was found to be that AdBlock was installed, so by either disabling the AdBlock add-on or whitelisting the Fubra site and hitting refresh, all image problems appeared to have been resolved – for now.

A quick solution was applied for anyone visiting the site with AdBlock enabled in order to avoid the hiding of imagery.

For now I’ve renamed the images and it seems to have solved the problem.

I found it very interesting that the AdBlock extension would automatically block localised images simple because they contained the phrase ‘advertising’.

It seems to me that the add-on may be acting a little greedy here and should maybe only exclude images from third party websites containing this phrase or similar phrases if any.

After all, adverts are usually put in place for a reason and in a lot of cases without them it’s unlikely that the site would be there at all.

3 Replies to “FF AdBlock add-on blocking local images”

  1. Neither Adblock nor Adblock Plus block anything “automatically” – it always happens according to the list of filters the user has defined. Since the user isn’t aware of adding that filter, he probably uses one of the pre-made filter lists. For Adblock there is only Filterset.G, for Adblock Plus there is a bunch of them (http://adblockplus.org/en/subscriptions). At least EasyList (most popular filter list for Adblock Plus) doesn’t have a filter for the word “advertising” – and in general filter list maintainers tend to fix false positives. Though in that case it is hard to tell whether it actually is a false positive…

  2. Wladimir, thanks for your response and clarification on this matter. It turn’s out that Filterset.G was in fact in use on the user’s machine, explaining the results achieved here.

  3. I did actually note in the original email that I was using the Filterset.G filter list, and curiously it also doesn’t seem to contain a generic match against simply the word “advertising” nor the relevant domain so I’m not actually quite sure what it’s matching on, and going to have to take a better look.

    The intention is not to fault Adblock/Plus so much, more to point out the obscure situations that can arise as a result of their use, no matter how widespread, and how best to avoid them for the sake of consistency on our websites. Your defence of Adblock Plus, though admirable, is rather unnecessary.

    And yes, it is a false positive.

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