The featured images in Luminance were completely misaligned due to
changes in how Gutenberg has changed the specifity of style rules.
Rather than the custom block-specific CSS for the core/featured-image
block taking priority, the default block library styles did.
The problem has been reported upstream
(https://github.com/WordPress/gutenberg/issues/64453) but in the
meantime, using the theme-wide custom CSS fixes the problem.
* Lossless image optimization (using ImageOptim).
This shouldn't change the visual appearance of any images. ImageOptim
was run with the highest compression setting except that JPEG metadata
stripping was disabled because some users prefer to avoid stripping
JPEG metadata.
* Update READMEs that have Changelogs for themes impacted by lossless image optmization change.
* Luminance: Add theme
* Fix typo and spacing in style.css
* Luminance: Minor adjustment for post titles
---------
Co-authored-by: Sarah Norris <sarah@sekai.co.uk>
