Hi Ferran,
sadly I have no separate testing-system yet.
But I created a simple new block chapter page with a simple graphic:
<!-- wp:paragraph -->
<p>test</p>
<!-- /wp:paragraph -->
<!-- wp:image {"id":1876,"sizeSlug":"full","linkDestination":"none"} -->
<figure class="wp-block-image size-full"><img src="https://pothimobil.eu/wp-content/uploads/2023/01/20221231T124519_v1-e1672592840673.jpg" alt="" class="wp-image-1876"/></figure>
<!-- /wp:image -->
The error message when choosing output format DOCX for this page is:
“Could not load image image_1673005053_969252447.jpg”
A totally different filename that is not within the page. Where does this come from?