This is weird but it looks that it only happens when you try to open a file with the WPS application from the files explorer (Caja in my case). If I open the application directly from the applications menu the icon is shown in Plank.
This is weird but it looks that it only happens when you try to open a file with the WPS application from the files explorer (Caja in my case). If I open the application directly from the applications menu the icon is shown in Plank.