fixing the redownload image when changing the appearance color

Hi,

I am looking for someone who can help me to fix the issue that image has been cached is getting download and cache again unexpected.
Here is how to reproduce:
1. Launch the app
2. let it finish loading the image
3. go to settings and change from Light to Dark on display & brightness
4. go back to the app
5. Observe an issue that cached image is getting download again unexpected

*Expected:
Should not redownload when it's ready cached.