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Polyfill.Io Cheat Sheet

[Optimized] Extra features

<script>if(!(window.fetch&&window.Promise&&[].includes&&Object.assign&&window.Map)){document.write('<script src="https://cdn.polyfill.io/v2/polyfill.min.js?features=default,fetch"></scr'+'ipt>')}</script>
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This is the same as the previous, but also adds a polyfill for window.fetch(). We add a window.fetch check and loads the additional fetch feature.

[Optimized] For modern browsers

<script>if(!(window.Promise&&[].includes&&Object.assign&&window.Map)){document.write('<script src="https://cdn.polyfill.io/v2/polyfill.min.js"></scr'+'ipt>')}</script>
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This only includes polyfill.io when necessary, skipping it for modern browsers for faster load times.

[Usage] References

[Usage] Default usage

<script src="https://cdn.polyfill.io/v2/polyfill.min.js"></script>
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This is the default script for Polyfill.io.

Reference

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