GORDON142 JCraig: True, but Opera stands alone as an almost completely inextensible browser on the Mac — There really isn't a way for third-party developers to add support to it.
Opera lacks a plugin interface like Firefox, but it is also not a Cocoa application like Safari. With cocoa applications, developers can "inject" code directly into the application through the use of input managers (there are problems with these, but they do allow just about any application to be extended). With no input managers and no plugin framework, there is little a third-party developer can do. This is a definite barrier to wider adoption, and it is something only the developers can address.
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