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I've detected changes to the following themes in this PR: Lexionic.
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@henriqueiamarino Here are my notes. The number of things I need to mention is getting less and less. Great job!

• I've noticed that the custom spacing sizes defined in the theme.json aren't working. If the JSON file is version 3, the defaultSpacingSizes must be false to override the default spacing size. Example. I reviewed the theme as if the custom spacing sizes are actually working, but please fix it in the next update.
• Most of the custom duotones aren't used in the theme, do we need them?
• I like the unique-looking CTA in the footer, but it's not looking great on small screens. Can we take a different approach to make it work on both large and small screen sizes?
  
• It's not a problem, but why do the images on the blog home template use the cover blocks but not the image blocks?
• It's probably better to use a heading for the text "Homer". It's awkward in the variations that use a font with a strong character for headings.
  
• A main tag is missing in all templates.
• Remove the following unused patterns. patterns/single.php, patterns/page.php,
• All the style variations have custom duotones. Do we actually need them? If we do, it's probably better if they were registered in the default json.
• Change the Requires PHP: to 7.2 in both readme.txt and style.css
• Let's add credits to the rest of two images bundled with the theme.
• Thanks for paying attention to the theme tags! You can also add block-styles and full-site-editing.

Thanks @iamtakashi. Although the check has failed, I believe I fixed all the issues.
Here's the checklist:

• I tried to fix the custom spacing sizes issue by adding the line defaultSpacingSizes: false. I am not sure if this is enough. Please let me know;
• I removed all the duotones. They belong to an initial idea that is now gone. I did it on the style variations, as well;
• The footer CTA was repaired to look better. Thanks for checking it;
• I am using a cover instead of an image to ensure the aspect ratio is set to 3:2. We can't control AR on images; we can only upload cut ones. But that would be a hack, and users wouldn't follow it. Do you think this is a problem?
• Made the author's text into a Heading;
• Added a main tag to all the Content wrappers;
• Removed the unused patterns: single and page.php;
• Changed the Required PHP to 7.2;
• Added the credit to the image that was missing;
• Added the extra tags you mentioned.

@henriqueiamarino, thanks for the update! Most of the issues were addressed correctly 👍

• Thanks for removing the custom duotones, but it's still used in here and here.
• The credit for the shadow image is missing.
• The height of the button is now different between the block variations. You have fixed the same issue here. However, this time, the border thickness is 2px.