Horizon theme squashes content of app block

Hello,

I’m encountering an issue with the Horizon theme and my app block: the content does not expand to full width and instead remains aligned to the left. For comparison, on other themes the same app block stretches across the entire page:

Horizon:

Other themes:

In Horizon, I have confirmed that the section is set to “Page width” in the theme editor:

As a temporary workaround, I added this CSS:

.shopify-block[data-block-handle="review_widget"] {
  width: 100%;
}

That forces the block to stretch, but it feels like a workaround rather than a proper solution, since it overrides core theme behavior.

Could someone advise on the recommended approach for ensuring an app block in Horizon can occupy the full page width? I appreciate any guidance or best practices.

Thank you

This sounds related to Bug: Horizon app blocks in header are not full width

@Luke Yes, you are right, it sounds related! However, the solution suggested there is similar to the workaround I have and does not resolve a root cause of the issue