Status of this document: in progress
Prettier by Christopher Chedeau is the de-facto community standard for (opinionated) code formatting web development source code of all kinds and by that ensuring code conventions.
The community is providing a lot of editor/IDE support, a lot of languages are being supported and you could start right away as it works out of the box.
There’s clearly no good reason to use spaces over tabs within your code - but a lot that speaks against it, as pointed out by the XO authors as well, but involves topics like accessibility as well. So we’ve chosen tabs as the standard for indentation as this is its general purpose. see also: https://twitter.com/_developit/status/968347230716547075