In https://meta.wikimedia.org/wiki/Talk:Interwiki_map#Etherpad it is proposed to change the path of the interwiki "etherpad:" from https://etherpad.wikimedia.org/$1 to https://etherpad.wikimedia.org/p/$1
This would break links of the bare form "etherpad:" with no path, though. The easiest way to fix this is probably to redirect the URL https://etherpad.wikimedia.org/p/ on the Etherpad server side to https://etherpad.wikimedia.org
If I'm reading both correctly the request in the task is the opposite of the one in the wiki discussion. Looking at https://meta.wikimedia.org/wiki/Interwiki_map/list, the request in the task is incorrect.
Yeah, the wiki discussion was right, and I got it backwards when I filed the task.
The proposal is to change the path to https://etherpad.wikimedia.org/p/$1 instead, thus the actual request (in the title and the last sentence) still describes what I want done.