it seems that some people have problems downloading (and using) the list of AUR packages. this is done in the beginning of the “install packages” option.
internally, this command gets used currently (in version 1.9.2):
wget -P "/tmp/aur/" "https://aur.archlinux.org/packages.gz" &>/dev/null && gunzip -f "/tmp/aur/packages.gz" && cat /tmp/aur/packages
i have recently adjusted this command, because the old command stopped working. the old command i have used was:
wget -P "/tmp/aur/" "https://aur.archlinux.org/packages.gz" &>/dev/null && cat /tmp/aur/packages.gz
i have tested both commands and on my systems (manjaro with bash/zsh and arch linux in VM) only the upper command is working.
if your experience is different, we have to find the cause of your problem.
when doing some tests, it might be worth to delete the aur folder in your tempfile directory before running each command listed above.
sudo tm -r /tmp/aur/