An upcoming release of Google Chrome will fully support animated PNGs, a Googler has said in the comments of a bug report ticket on the Chromium website.
Extensions available via the Chrome Web Store have long added support for animated PNG, but this Googler says that Chrome 59 will not require any extensions.
One person asked:
Does this mean that Chrome will now have full apng support without extensions?
The which this Googler replied:
Yes, Chrome 59 animates animated PNGs without requiring any sort of browser extensions.
The current stable version of Chrome is 57, and version 59 is currently in the Dev Channel. You can opt-in to the Dev Channel here.
Animated PNG, or APNG for short, is a relatively new file format that functions similarly to GIF. Unlike GIF, however, APNG supports both 24-bit images and 8-bit transparency.
References to ‘Add support for animated PNGs’ first appeared in the Chromium open source Google Git in March, but this is the first confirmation that the feature will publicly launch with Chrome 59. Requests to add the feature to Chrome go all the way back to 2008.
Some browsers, including Firefox, have long supported the format. But APNG has been gaining mainstream popularity as of late, particularly since Apple chose to adopt the APNG file format for iOS 10 iMessage apps.
To get a clue as to why it took Google so long to adopt APNG, you can read a 2013 conversation between Google developers here.