I think it might be possible editing some settings on the registry. Can anyone tell me what I have to edit? So the shell methods will be the same for RAR and XPI files...
Open Winrar's Options > Settings > Integration tab. Inside the "User defined archive extensions" box, type .XPI and click OK. Windows 7 will request your permission to change system settings. Click Yes and you're done.
Options > Settings > Integration
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3 years ago