Two important points: 1) we're using jobs inside of folders, sometimes up to 4 levels deep, 2) we're sending links in email notifications to our users for failed builds, etc. As it turns out Outlook 365 has ATP (Active Threat Protection) which wraps URLs from "unknown" or not specifically whitelisted addresses in another site controlled by MS.

I've confirmed using http://www.o365atp.com/ that the URL encoding for the full job path (i.e. /blue/organizations/jenkins/folder%2Fjob/detail/...) is correct in the wrapped link.
Unfortunately, their ATP endpoints returns a 302 with a location that has been URL decoded one too many times, so that I end up with /blue/organizations/jenkins/folder/job/detail/...). This fails to load in blue ocean since it does not handle job paths with actual slashes instead of URL encoded slashes (%2F).

Obviously the best answer is that MS should fix their stuff, but I don't think that's going to happen anytime soon. I can also workaround this by using nginx rewrites since we are behind nginx. However, those rewrites are messy and difficult to get right for arbitrary depths of folders.

IMHO, blue ocean should be able to handle paths that are not URL encoded for jobs, since there are markers before and after the job (/jenkins/ and /detail/, etc). Is there a chance that we could improve the URL routing to handle this? I'm happy to take a look myself, but I'm not sure where the actual routing is being done for blue ocean.