Preview styling for pages is broken

[osmers]

Describe the Bug

The preview function for pages does not reflect how the content will look in the app. The styling is broken.

Steps to Reproduce

1. Go to https://admin.integreat-app.de/ammerland/pages/de/36617/edit/
2. Check content and styling in the editor
3. Click on preview
4. See that the styling differs in the following points:
   a) Bullet points missing
   b) break after inserted icons, even though there are non
   c) headings are not visible as headings
   d) no breaks are shown between paragraphs
   e) links are not visually marked as links

Expected Behavior

Upon clicking on preview, see the content as it would look in the app

Actual Behavior

See the content as a sort of list without much styling.