Plus! should add this feature, it's not that hard to implement. Espically if the skins had to be packaged. I mean if Plus! had it's own extension all you would need is the details of the skins, e.g. name, compatible with Messenger versions etc and the .res file.
In theory the mechanics is not that difficult to apply, and in terms of a feature it would certainly be worth it, mainly because skins no longer have installers, and I'm constantly getting emailed on how to install one particular skin. Plus! allowing 3rd party skins to load onto Messenger would be nothing far off amazing
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