Animated Gifs in banners stopped working
Noticed a little while ago that the banner we use for our affiliate link to 1&1 Internet was not being displayed in our page footer.
Further inspection revealed that 1&1 Internet had changed their affiliate specification slightly (not that we were informed but there you are!). Anyway they now provide animated GIFs to use so replaced our 'old' configuration with the suggested new details.
That was fine apart from the link still refused to display. So we had to investigate further. What didn't help was that we were unsure exactly when the link first exhibited problems, so were unsure whether this was caused by a change of ours, or just by 1&1.
To cut a long story short, we discovered that it was the animated GIFs that were causing the problem, since a static image displays fine. For our purposes a static GIF is fine, and until we have more time to see if the animated GIF problem is more widespread than just banners it will suffice.