On Arch Linux PCManFM shows applications when I go to menu://applications in it, without a problem. I do not think I even had to configure it to do this. On Gentoo and Void, however, this does not happen out-of-the-box. Is there a way to get PCManFM to show applications when opened to menu://applications on these other distributions? For example, do I need to install extra applications or compile some packages with different options on Gentoo?
Based on https://wiki.archlinux.org/index.php/PCManFM#No_.22Applications.22 I decided to delete all files in ~/.cache/menus and restart PCManFM. It did not work. Granted that was the Arch Wiki and Arch seems to work perfectly with respect to PCManFM.