Add Accessibility and other user preferences to the Editor on-boarding flow

[jameskoster]

For full details, please take a look at this post on the make blog.

Otherwise a TLDR is: important user preferences are somewhat buried in the UI, and we could improve a users 'first-touch' experience if we gave them the option to configure these preferences right away.

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Here's a video demonstration of a design that could work:

welcome.mp4

The existing welcome guide is condensed down to a single frame, and subsequent frames expose preferences organised by category. For each option, a visual preview is revealed on hover.

A technical challenge here is to avoid relying on graphical assets whose appearance will go stale over time. I put forward the idea of rendering the actual components here, but I'm unsure how feasible that is. Another technical consideration that came up in the comments of the original post is whether to allow third parties to extend the on-boarding flow. On the surface it sounds like a nice idea, but could be open to abuse. Let's discuss.

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It's worth noting that some of the options in the video above (Document Toolbar appearance and Inline Text Tools) haven't been fully implemented just yet, but I don't think that has to prohibit us from working on this. Those options can easily be added at a later date.