I installed v4.0.2 and it's working fine now with me, Only adding 2 Yahoo accounts not working fine, sometimes Yahoo ask me to change my password and no option to open the Email without it but if i wait for sometime i can open it normally, i think it's not the addon problem, Thanks for your work
BTW i'm using FT DeepDark theme and the addon menu looks black like the theme is there a way you can change the colors or add option so we can change colors?

Thanks Again