Safari won't open images on some websites -
Safari won't open images on some websites - a question mark is in the image? Also Develop is a new tab and I have no idea what should or shouldn't be ticked?
MacBook Pro 13″, macOS 10.13
Question marked as
First please review If Safari on Mac doesn't open a webpage or isn't working as expected - Apple Support, and if none of that gets you anywhere, the following two documents:
Clear your browsing history in Safari on Mac - Apple Support
Manage cookies and website data in Safari on Mac - Apple Support
You can show / hide the Develop menu in Safari's Preferences... menu > Advanced tab.
Before you disable it though, try scrolling to the bottom of the Develop menu's Experimental Features selection, and select Reset All to Defaults. That answers your second question.
If the images still fail to load, I have another suggestion. There have been scattered reports of WebGL having trouble with Metal. I'll have to find them again. The solution requires disabling that option in the Develop menu. Now that you know where to find it, that should be easy to try if necessary.