Add/Remove Software opens up to an empty Featured view when opened via the tray icon provided by this package.
After an update to pamac pushed out to Testing branch on December 26th, clicking on the pamac-tray-icon-plasma tray icon brings up pamac with an empty view, like so: Switching to “Installed” or “Updates” and back brings back the featured applications, as does selecting something under “Browse by” or “View”, and going back. Doing a search and cancelling it works as well.
Launching pamac (or “Add/Remove Software”) through other means, such as krunner, via terminal etc., does not cause this visual glitch, and featured applications are visible right away.