getting Red background in Safari I'm getting a strange red background when I visit some pages using Safari. 
on Chrome the page is rendered in white normally.

I am not using any extensions and plugins. 

How do I fix this bug?

Safari: Version 10.1.1 (12603.2.4) 
macOS: Sierra Version 10.12.5



Edit: I do not have the paint flashing feature turned on, I also noticed that this bug occurs on local images with a transparent background without any stylesheets (see image below). 

I tried opening a local file image, and it opens normally on Chrome and Preview. However on safari, the images has a red background.
I think this is a feature for web developers called "paint flashing".

Right-click on a blank bit of a page and select "Inspect Element", this will open the Web Inspector in Safari.

In the top-right corner of the Web Inspector there are a few icons. One looks like a paint brush. On your machine I bet it is selected.

Click it to turn it off.