MIdbrowser will stay "Work Offline" when use wireless NIC

Bug detailed description:
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When I use wireless NIC,though I configure it correctly and confirm it can connect to internet,Midbrowser will remain stay offline.If launch Midbrowser,I can see that "Menu->Work offline" is checked,but if make it unchecked,Midbrowser can surf the internet again.It means every time I launch Midbrowser,"Menu->Work offline" is always checked.
This issue won't happen when use a wired NIC,so I think Midbrowser perhaps was not able to recognize wireless NIC.

Reproduce steps:
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(1) Unplug wired NIC and plug wireless NIC
(2) Launch Midbrowser,note that "Menu->Work offline" is checked
(3) Make "Menu->Work offline" unchecked,then can surf the internet again
(4) Close Midbrowser and launch it again,note that "Menu->Work offline" remains checked

Current result:
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Midbrowser submenu "Menu->Work offline" is always checked when use wireless card.

Expected result:
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Midbrowser submenu "Menu->Work offline" should change the status also according to the status of wireless card.

Basic root-causing log:
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