This PR removes the `visibility` style property change from next/image. It was previously added in #18195 to fix a bug that when no `src` is set, and that bug is not valid anymore as all images will always have `src` (and a fallback too).
It also fixes the problem that screen readers ignore elements with `visibility: hidden`.
Fixes#23201.
## Bug
- [x] Related issues #23201
- [ ] Integration tests added
## Feature
- [ ] Implements an existing feature request or RFC. Make sure the feature request has been accepted for implementation before opening a PR.
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
## Documentation / Examples
- [ ] Make sure the linting passes
Currently, the image component doesn't handle use of the `sizes` property with `layout="fill"` and `layout="responsive"` very well for small viewports. It will never include sizes smaller than the smallest viewport (640px) in the srcset, so even if you specify `sizes="30vw"` in your image, you have to download the full-viewport-width image on small devices.
This PR adds logic such that if you use `layout="fill"` and include a `sizes` property, the image component will include the full range of image sizes in the `srcset`.
It also includes an optimization where it finds the smallest `vw` value in the sizes value and combines that with the smallest viewport width, and uses that as the floor of the srcset. It does this so it doesn't unnecessarily increase transfer size by including ALL sizes. This is still a conservative optimization--for 95% of cases, taking the _largest_ `vw` size would work, but I don't see a way to do that without breaking a few corner cases.
The case of a sizes prop with `px` values is fixed but not optimized--though generally that case is less of a good fit for the fill or responsive layout anyway.
This ensures the default path used for the `next/image` component includes the `basePath` when configured. Additional tests have also been added to ensure the image component is working correctly with `basePath` configured.
Fixes: https://github.com/vercel/next.js/issues/19711
