The issue has been located.
IDM doesn't allow unknown browser to connect to its server, so the menu item has been disabled.
Please follow this instruction to add centbrowser to IDM's browser list:
http://www.internetdownloadmanager.com/r.../bi13.html
or as a temporary solution, you can simply change centbrowser.exe to chrome.exe
IDM doesn't allow unknown browser to connect to its server, so the menu item has been disabled.
Please follow this instruction to add centbrowser to IDM's browser list:
http://www.internetdownloadmanager.com/r.../bi13.html
or as a temporary solution, you can simply change centbrowser.exe to chrome.exe