- M-x permission-manager

Results in the following backtrace:

TypeError: host is undefined
chrome://conkeror/content/permission-manager.js:102
@chrome://conkeror/content/permission-manager.js:102:1
_co_impl__send@chrome://conkeror/content/coroutine.js:415:25
input_handle_command@chrome://conkeror/content/input.js:341:9
@chrome://conkeror/content/commands.js:162:13
timer_callback.prototype.notify@chrome://conkeror/content/timer.js:16:9

This occurs if there are any entries in the permissions.sqlite. 

My guess is that it is related to this controversial move (what decision of Mozilla's isn't controversial
or inexplicable these days?) to remove centralized control over permissions via the about:permissions page:

https://bugzilla.mozilla.org/show_bug.cgi?id=933917