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---
title: Dark Reader breaks image view in Firefox
subtitle: Use this workaround to view the whole image.
date: 2019-06-28
tags:
- firefox
- firefox-ext
---
When using [Dark Reader](https://addons.mozilla.org/en-US/firefox/addon/darkreader/) (DR) add-on with "Filter" or "Filter+" mode in Firefox (FF 67 as of writing), you may encounter this issue where only the lower half of an image is shown.
{% cloudinary '20190628/dark-reader-before.png' 'Image is only shown half' %}
To resolve it, add the following CSS rule to the DR's setting via **Dev tools**. Prepend before the site-specific rules.
```css
@media not print {
img {
bottom: auto;
}
}
```
{% cloudinary '20190628/dark-reader-dev-tools.png' 'Dev tools of Dark Reader' %}
{% cloudinary '20190628/dev-tools-video.webp' 'A video of Dev Tools' %}
After adding the CSS, you should be able to see the whole image. But the fix is not perfect, the image sticks to the top rather than centred.
{% cloudinary '20190628/dark-reader-after.png' 'Full image is shown' %}
The above CSS is to override the default CSS used by FF to display an image. The default CSS is located at `resource://content-accessible/TopLevelImageDocument.css`, accessible via Style Editor (Shift + F7, don't enable Caret Browsing when prompted). It's used to centre the image. Here is a snippet of "TopLevelImageDocument.css",
```css
@media not print {
img {
text-align: center;
position: absolute;
margin: auto;
top: 0;
right: 0;
bottom: 0;
left: 0;
}
2019-06-29 09:29:06 +00:00
}
```
The `bottom: 0;` rule is the source of the issue, though it's more of a compatibility issue between DR and FF.
I got the information from the issue report ([#1142](https://github.com/darkreader/darkreader/issues/1142)). It's unlikely that the fix will be in the default DR, so you need to re-apply the workaround every time DR is updated.
Credit: Screenshots and screen recording contain a photo by [Yunming Wang](https://unsplash.com/@ymwang) on [Unsplash](https://unsplash.com/photos/GY2udBfnA6k).