Note from 6 November 2020

Do anyone know why Google made it mandatory for #PWA icons to be PNG, not JPEG or other?

This is what #Lighthouse requires, but I couldn't find any docs about this. #MDN says other formats are fine.

6 reactions

Matt Hobbs
If I had to guess I'd say because of the alpha channel availability? Since you don't know where the icon is going to be embedded.
- 7 November 2020, 00:00
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Nicolas Hoizey
Why not SVG, then?

And with masks, is it really necessary?
- 7 November 2020, 00:38
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Paul Irish
Chrome used to require PNG. But that got sorted a bit ago. We have a change coming to Lighthouse to have it aligned on these PWA requirements. github.com/GoogleChrome/l… related issue
- 7 November 2020, 00:45
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Maximiliano Firtman
I'm not sure why you might prefer JPEG for an icon but I guess it has to do with platform restrictions. Most underlying platforms use PNG as the icon format and with that the browser doesn't need to touch your icon.
- 7 November 2020, 00:55
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Nicolas Hoizey
Ok, thanks! 👍
- 7 November 2020, 10:27
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Nicolas Hoizey
I would prefer JPEG for weight, or even WebP, or SVG when possible.

I understand PNG is the easiest to support.

I also know Lighthouse only considers Chrome’s requirements.

Is there any resource about image formats supported by main platforms for icons?
- 7 November 2020, 10:29
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