dmenu mode is inefficient at loading menu options #22
Description
When using dmenu mode and loading a large number of options (26000 in my concrete example) loading these takes a significant amount of time for all options to become available. For example, for the 4000th option to become available it takes around 10s.
Additionally, it is not very transparent that not all options are available yet, since the options just don't show up and it is not signaled to the user that some are still missing.
Overall I would expect this to take a much shorter time, since in their totality the options are only around 4KB so it's not like I am loading gigabytes of options either.
To make testing easier I have attached the file I was using: nixpkgs_names.txt
Edit: the 20,000th line takes over 5 minutes (I gave up waiting). Also while an option hasn't been loaded it can't even be entered manually as some other option will be returned instead.