This comment by yurishimo should not be [dead], imo

>Just a heads up but datalist is not really a great solution if you need a strong contract. The user can still type whatever they want into the field and there is no fuzzy filtering or typo mitigation. Once you add those requirements, a library that gives you a more fully featured combobox is likely going to make a lot of sense in your project.

It is true! HTML can do a lot of cool stuff, it might get you 100% of the way depending on what you're doing. But if you have a lot of forms where users pick from a value set, and want to enforce no other strings and get a good search experience, datalist does not get you there.

I seem to recall there was a proposal to add such thing to <select>s

(iirc if you have [showdead] on you can click on the timestamp to the comment and will get a [vouch] option as a reverse-flag, fwiw. i see it and don't have showdead enabled, so enough people have re-vouched it!)