Bouncer links fail to activate client if page's canonical URL doesn't match its actual URL

Bouncer links fail to activate the browser extension if the URL that bouncer navigates the browser to ends up redirecting to a different URL with the same content.

One case where this can happen is if a URL A declares a canonical URL B which redirects to URL A. For example https://www.pfrazee.com/blog/why-facets declares a canonical URL of https://pfrazee.com/blog/why-facets. That canonical URL redirects to the `www.`-prefixed version. When annotating on this page, the canonical URL is used as the annotation's URL. When bouncer detects the extension and asks it to navigate to this URL and activate the client, it will initiate the navigation and then schedule a "pending activation" once the client arrives on the target URL. However since the URL immediately redirects, the user never lands on the expected target URL (ie. the page's canonical URL) and the pending activation is never applied.