Claws mail updated quite frequently recently but I found that the Gtkhtml2 Viewer plugin was no longer there.(it used to be there when I fist install Claws Mail.) I go to Claws Mail website and download the plugin, it is zip file which I an unzip them on my pc and got a folder gtkhtml2_viewer-0.19, but I don't know how to install this plugin, or where to put this folder. I checked the manual for claws mail and it says the plugin file is with .so but I couldn't find any file end with .so

I wonder if anyone can help me explain in detail how to install the plugins to the claws mail.

Thanks

Gary