What causes the IE browser to detect compatibility view

Question

I've noticed some websites IE will automatically trigger to display in compatibility view, but once you disable it, it won't auto-trigger anymore. How do you make the browser reset this behavior so it will go back to how it was before it was disabled, to see if it auto triggers it or not?

I've tried clearing it out in websites to view in compatibility view and it still doesn't reset its behavior of auto-triggering compatibility view.

Answer 1

It often happens when a doctype either isn't set, or is set incorrectly. Plus, even if a doctype is set correctly, if PHP or manual code entry leads to anything being output before the doctype, it can also cause this issue.

If you press F12 you should get the Developer tools. There is a drop-down menu at the top titled "Browser Mode" - in there you should find compatibility view. Also, restarting IE can sometimes work for me.