Hi Longfei,
I am running Moodle 3.1.2. I copied the lib.php and locallib.php from the Bitbucket repository you referenced and put these files in the mod/forum folder but when I tried it, I could not see any of my courses or any menus. Did I put the files in the wrong place or am I missing other files to make this work?
Thank you for your help. I would love to be able to use this pluggin!