This is quite a simple bookmarklet, as most of mine are.
The sole purpose of it is to check whether fields that you would expect to be programmatically
grouped are done so correctly. It looks for the obvious HTML construction, such as `fieldset`
and `legend`, but also looks for roles of `region` or `group` and checks whether there is an
`aria-label` or `aria-labelledby` by for that group. It then visually highlights the grouped elements
on the page. Because of the nature of the script, it will also highlight other regions that are
grouped in the same way, but you just have to ignore that. Just focus on the parts of the page
that you actually want to check. As ever, my reason for making this was so that I can quickly check
and then take a screenshot to verify that it has been done correctly.