When reloading settings page, white background appears when using dark theme

### Issue Details

- **AdGuard version:**
- 4.1.39
- **Browser and version:**
- Chrome 107
- **Operating system and version:**
- macOS 13
- **Filters you use in AdGuard:**
- N/A
- **Stealth Mode settings:**
- N/A
- **Other browser extensions:**
- N/A

### Expected Behavior

When opening and reloading the settings page, a white background doesn't appear when using a dark theme.

### Actual Behavior

When opening and reloading the settings page, a white background appears when using a dark theme.

### Screenshots

Screen recording

https://user-images.githubusercontent.com/19418601/199544784-a8610f2b-d902-4158-986c-5423ad7b4ced.mp4

### Additional Information