Brows­er, brows­er on the wall, who has the worst fea­tures in all the land? JavaScript, of course!

This ses­sion scours the JavaScript and DOM spec­i­fi­ca­tions for the worst fea­tures from JavaScript’s long his­to­ry. Find out which encrust­ed lega­cy fea­tures from the chalk age of web stan­dards are still avail­able in the lat­est Chrome beta, which fos­silized syn­tax acci­dents are still lurk­ing in every­day data struc­tures and which absurd hacks both grey­ing brows­er war vet­er­ans and the React kids from the bleed­ing edge have used and are still using.

The JavaScript fea­tures from hell not only have plen­ty of hor­ror fac­tor to offer, but are also instruc­tive, worth know­ing and some­times the only way to solve prob­lems. Find out which mis­takes from the pri­mor­dial soup still result in car­go cult pat­terns today, why React throws promis­es instead of excep­tions and take a look at a whole lot of code that you (hope­ful­ly) won’t see any­where else.