Since this is dependent on an upstream feature request that hasn't seen any activity since 2014 I also suspect it isn't going to happen.

But @kugel-, since setting your "pending timeout" label does not prompt anybody, you need to also post some text to tell those watching that you have put their request on a short fuse unless there is some indication of activity, so that they know about it and can object if they are still interested. It is unreasonable to silently put a target on the request without notifying anybody interested before pulling the trigger.