As the title suggests, I've found that exceptions added for 'Enhanced Tracking Protection' simply do not function in a private window; they're entirely ignored. The discovered 'Tracking Content' (from shield in the address bar) will list the exact domain that's whitelisted and the network tab of the devtools will label the URL as blocked due to tracking content. Obviously this is wrong, that short of per-window type settings, this should be global (and makes no sense to differentiate anyhow).

Switching to a standard window fixes this, however, and the exceptions are taken into account.