Save theme color change and save image button after opening an image

**Is your feature request related to a problem? Please describe.**
I think it would be nice if the color of the save would change based on your theme. Ex: screenshot below.

Have an image download button after opening an image.

**Describe the solution you'd like**
A switch in the "Appearance" -> "Themes" -> "App Theme" tab to flip it between either being green or the color of the theme.

A switch in the "General" -> "Other" tab to flip it between the image share button with the image download button.

**Additional context**