Improve favicons to match www.python.org

[hugovk]

The Python favicons on https://docs.python.org (and https://pip.pypa.io etc.) are much lower resolution than on https://www.python.org

Here they are, docs on the left, www on the right, on a Mac Retina screen:

---

The first commit here (5088726) adds favicon.ico from https://github.com/python/pythondotorg/tree/master/static/favicon.ico (containing 16x16, 32x32 and icons) and uses it for the basic favicon instead of the low-resolution 16x16px py.png.

---

The second (1b2f0e0) add the Apple touch icons and Microsoft Win8 tile icons, also from https://github.com/python/pythondotorg/tree/master/static, and shows them with the same markup as www.python.org:

https://github.com/python/pythondotorg/blob/65cb6aa6e9f2e2f87195e1997cfe74d32701c0be/templates/base.html#L41-L52

---

Finally, the third (471c170) copies the 57x57px apple-touch-icon-precomposed.png (the smallest new one) on top of the low-res 16x16px py.png which is shown inline in the header/footer breadcrumbs, and shows it also at 16x16px.

(So apple-touch-icon-precomposed.png and py.png are duplicates. Would it better to use a single filename for both? If so, what?)

---

Before

After

[hugovk]

(oops clicked the wrong button!)

Rebased on master to trigger a test on the CI. ✅

[JulienPalard]

I'm not a front-end dev, so feel free to ignore my comment.

Is this mandatory to use the name of a company to display a favicon? It looks so wrong to me.

[hugovk]

<link rel="apple-touch-icon-precomposed" sizes="144x144" href="{{ pathto('_static/' + theme_apple_touch_icon_144x144, 1) }}" />
<link rel="apple-touch-icon-precomposed" sizes="72x72" href="{{ pathto('_static/' + theme_apple_touch_icon_72x72, 1) }}" />
<link rel="apple-touch-icon-precomposed" href="{{ pathto('_static/' + theme_apple_touch_icon, 1) }}" />
<link rel="apple-touch-icon" href="{{ pathto('_static/' + theme_apple_touch_icon, 1) }}" />

Strictly speaking these aren't favicons but for the "Apple Touch Icon", which can for example can be used on the iOS home screen:

https://blog.notmyhostna.me/posts/set-apple-touch-icon-for-any-website/

An example from that blog, if there's no touch icon, a saved website looks like RaceFans here:

With a touch icon it's like:

The filenames can be anything (I followed the lead from https://github.com/python/pythondotorg/tree/master/static), but the rel=apple-touch-icon* bits are special Apple keywords:

https://developer.apple.com/library/archive/documentation/AppleApplications/Reference/SafariWebContent/ConfiguringWebApplications/ConfiguringWebApplications.html

[JulienPalard]

I'll gladly merge this without the close-source-specific bits.

[hugovk]

I'll gladly merge this without the close-source-specific bits.

Just to be clear, do you mean the four lines I quoted which specify what touch icon to use on Apple devices?

How about the lines for Windows tiles?

By the way, adding both https://www.python.org/ and https://docs.python.org/3/ to the Android homescreen shows this difference. I read that Android devices prefer another but can also use the Apple touch icon too:

The complete solution for full support would probably be to use something like https://realfavicongenerator.net/ to define all the files and metadata, but my approach was to follow https://www.python.org/ which has quite good coverage. But happy to remove stuff it you like, personally I just want a higher resolution icon for browser tabs and don't use homescreen bookmarks or Windows tiles. :) Thanks!

[JulienPalard]

Sry I stopped scrolling too soon, didn't even noticed Microsoft was selfishly spreading their name too. Let's wait 10 more years and it'll take hundreds of lines.

[hugovk]

Closing as:

• the theme now uses a scalable SVG favicon (Make the theme responsive #46) so now looks good on Retina screens
• I don't personally use any of the touch icons
• this PR now has conflicts