The donations page at http://www.spi-inc.org/donations/ contains an image linking to AmazonSmile (which by the way is not introduced in text). Text integrated in the image reads: "Shop at AmazonSmile and Amazon will make a donation to:", then there is a "Get started" button. There is no text between the text and the button, either in Firefox or Chromium. Below that image, the text "Software In The Public Interest Inc", which also seems stray, appears.
Presumably, some Amazon JavaScript running expects to find the text somewhere in the DOM and is supposed to move it inside the image. But - possibly because the location in the DOM has changed - this is no longer working, so the text stays at its initial position and does not get in the image.
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Philippe Cloutier
http://www.philippecloutier.com