Chris Wilton-Magras

We do have Puppeteer tests, but even running them with Jest is a touch awkward, as we seem unable to use "fake timers", meaning our tests need to await real-time...

This is likely redundant, now that [modern browsers largely support custom elements](https://caniuse.com/?search=custom%20elements). Note that Safari does support custom elements in the way they are used in this clapper component.

What devices do we need to support? A small mobile device is likely unsuitable anyway, but do we want to support tablets? @pgchamberlin Do we have a requirement for device...

Recommend doing #93 before this issue.