Boost carousel blurry

**Describe the bug**

Since a few weeks, I noticed that some posts in the boot carousel are very blurry. Often, this affects posts at the beginning of the carousel. When I scroll horizontally, later posts are sharp/clear. It looks like a rendering/scaling issue. I’m on Firefox (Ubuntu).

- Which site: phanpy.social
- Which instance: mstdn.social

**To Reproduce**
Steps to reproduce the behavior:
1. Go to Home Feed
3. Scroll down to a boost carousel
4. Some of them (but not all) show in a blurry way.

**Expected behavior**

The boost carousel cards should display the same sharpness like the rest of the site/posts.

**Screenshots**

Compare the boost carousel (esp. the 3rd post) and the posts above and below to see the difference in sharpness.


**Desktop (please complete the following information):**
- OS: Ubuntu
- Browser: Firefox
- Version: 117

**Additional context**

I noticed the problem for a while now, but I don’t think it was always there from when I started using Phanpy. So it might be a bug introduced at a later point.