import { options } from 'preact'; const classNameDescriptor = { enumerable: false, configurable: true, get () { return this.class; }, set (value) { this.class = value; } }; const old = options.vnode; options.vnode = vnode => { const a = vnode.attributes; if (a != null) { if ('className' in a) { a.class = a.className; } if ('class' in a) { Object.defineProperty(a, 'className', classNameDescriptor); } } if (old != null) old(vnode); };