Gutenberg: Blog posts added to Navigation area, displacing sidebar widgets

[pauljacobson]

Steps to reproduce

1. Starting at URL: https://lacavedestephane.com/vin-blanc/
2. The sidebar widgets for this page are displaced by what appear to be blog posts.
3. These posts are not widgets, and they only appear in this location on this page.
4. This apparently first occurred after the user added a block to their page. The new block doesn't appear to have any unusual code. Here's the HTML code for this particular block:

<div class="wp-block-media-text alignwide" style="grid-template-columns:28% auto;">
    <figure class="wp-block-media-text__media"><img data-attachment-id="1991" data-permalink="https://lacavedestephane.com/cha%cc%82teau-du-breuil-savennieres-blanc-2014/" data-orig-file="https://lacavedestephanecom.files.wordpress.com/2018/12/Château-du-Breuil-Savennières-Blanc-2014.jpg"
            data-orig-size="752,1345" data-comments-opened="1" data-image-meta="{&quot;aperture&quot;:&quot;2.4&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;iPad Air&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;1544539059&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;3.3&quot;,&quot;iso&quot;:&quot;125&quot;,&quot;shutter_speed&quot;:&quot;0.04&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}"
            data-image-title="©lacavedestephane Château du Breuil Savennières 2014" data-image-description="" data-medium-file="https://lacavedestephanecom.files.wordpress.com/2018/12/Château-du-Breuil-Savennières-Blanc-2014.jpg?w=168"
            data-large-file="https://lacavedestephanecom.files.wordpress.com/2018/12/Château-du-Breuil-Savennières-Blanc-2014.jpg?w=573" src="https://lacavedestephanecom.files.wordpress.com/2018/12/Château-du-Breuil-Savennières-Blanc-2014.jpg?w=573"
            alt="" class="wp-image-1991" srcset="https://lacavedestephanecom.files.wordpress.com/2018/12/Château-du-Breuil-Savennières-Blanc-2014.jpg?w=573 573w, https://lacavedestephanecom.files.wordpress.com/2018/12/Château-du-Breuil-Savennières-Blanc-2014.jpg?w=84 84w, https://lacavedestephanecom.files.wordpress.com/2018/12/Château-du-Breuil-Savennières-Blanc-2014.jpg?w=168 168w, https://lacavedestephanecom.files.wordpress.com/2018/12/Château-du-Breuil-Savennières-Blanc-2014.jpg 752w"
            sizes="(max-width: 573px) 100vw, 573px"></figure>
    <div class="wp-block-media-text__content">
        <h5><a href="https://lacavedestephane.com/2018/12/17/chateaudubreuil-savennieres-2014/">Château du Breuil – Savennières – Blanc –&nbsp;2014</a></h5>
        <p>Un vin charnu et concentré sur des notes de coing, de fleurs et de pomme verte. L’élevage apporte de légers arômes grillés et le terroir de schiste le côté minéral si caractéristique de l’appellation.</p>
        <p>Cépage : chenin.</p>
        <p>Région : Loire.</p>
        <p>Tarif : 19,95€</p>
    </div>
</div>

What I expected

The sidebar should appear in its correct location on the page. For example, on this page, this layout is correct:

What happened instead

Instead, it looks like posts are displacing sidebar widgets, right after the Navigation section, here:

Changing themes did not resolve this issue.

Browser / OS version

Reproduced on macOS 10.14.2, in Firefox Developer Edition 65.0b4, and Chrome 71.0.3578.98.

Context / Source

• User report: 8873517-hc
• Follow-up: 1651485-zen

[stale[bot]]

This issue has been marked as stale and will be closed in seven days. This happened because:

• It has been inactive in the past 9 months.
• It isn't a project or a milestone, and hasn’t been labeled `[Pri] Blocker`, `[Pri] High`, `[Status] Keep Open`, or `OSS Citizen`.

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