fix skull png

[advaith1]

Hi, I'm Advaith from Discord. I got a report from a user that the skull emoji appears differently on Android vs desktop, particularly the eyes are different shapes. It seems to be because the PNG image is different from the SVG image. On desktop we use the SVGs but on Android we use the PNGs.

PNG	SVG

I used rsvg-convert to convert the skull's SVG to PNG so they are consistent now. However, this seems to have increased the file size significantly - is there a preferred way of optimizing the PNG?

[jdecked]

Hi @advaith1, thanks for reporting this! Usually we run the PNGs through ImageOptim at the highest compression, then confirm the compressed & original PNGs visually match. Happy to merge this once you've done that, and I assume you'll need a patch version to be published on NPM too?

[advaith1]

Thanks, compressed!

re npm, it looks like the png files are not published to npm? We pull them from our GitHub fork.

[jdecked]

re npm, it looks like the png files are not published to npm? We pull them from our GitHub fork.

They aren't, but they're referenced in the code through a CDN that pulls from GitHub tags. If you just pull the images alone from your own fork/don't use the referencing code, it should be fine (unless you also rely on the tags somehow). I'll merge this now (from mobile). Let me know if you need anything else.

[12Me21]

Actually, the png was correct, it's the svg that is wrong here.
#34
Several emojis have shapes which were incorrectly replaced with circles/ellipses by an "optimization" many years ago
(the reason the png became desynchronized in the first place was because the svg was mistakenly changed, during an operation which supposed to reduce its filesize without changing the appearance, so they didn't re-render the pngs)
Generally: there isn't really any sequence of events which can lead to an incorrect png in twemoji. When there is a discrepancy, it's almost certain to be the svg which was accidentally changed, while the png remains correct because it was never re-rendered.