mediawiki.action.view.redirect.js is not idempotent when used on double redirect, on a wiki where $wgMaxRedirects is 1 (the default). Refreshing the redirect page redirects the user further in the chain.
To reproduce, create redirect chain A → B → C, then visit A. Observe that you're seeing B. Refresh the page, you're seeing C now.
We probably need to add ?redirect=no to the URL in some cases.