Smallest data URI image possible for a transparent image

After playing around with different transparent GIFs, some are unstable and cause CSS glitches. For example, if you have an <img> and you use the tiniest transparent GIF possible, it works fine, however, if you then want your transparent GIF to have a background-image, then this is impossible. For some reason, some GIFs such as the following prevent CSS backgrounds (in some browsers).

Shorter (but unstable – 74 bytes)

data:image/gif;base64,R0lGODlhAQABAAAAACH5BAEKAAEALAAAAAABAAEAAAICTAEAOw==

I would advise using the slightly longer and more stable version as follows:

⇊ Stable ⇊ (but slightly longer – 78 bytes)

data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7

As another tip, don’t omit image/gif as one comment suggests. This will break in several browsers.

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