@Erik Vik Sorry about the issues you are having accessing notebooks. I looked at your account and there isn't anything on our end which should be causing this. Not connecting or a blank screen (often accompanied by the 403 or FORBIDDEN error) is typically a browser settings issue. Quantopian's research environment relies on third party cookies and cross site tracking to protect user's intellectual property. Those two features must be enabled in your browser. Not having these enabled can cause issues. Additionally, for similar reasons, one cannot access notebooks from an 'incognito' window. There have been a number of updates to common browsers lately which may have changed past settings.
In the Firefox preferences, find the cookies and site data menu. Check the box that says "Accept cookies and site data from websites" and make sure the box that blocks 'Third-Party Cookies' is unchecked.
If none of these things work for you, please try disabling all extensions, and re-enabling them one a time to find which one may be causing problems. If you find one that is causing the Quantopian site to break, try whitelisting
dynoquant.com (those are the two domains that Quantopian uses).
You may also contact support if you're still experiencing problems.
Again, sorry for the inconvenience.
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