There doesn't seem to be any support for using a different GSA collection per locale. We initially thought we'd just make the collections variable a multilingual variable but that failed because of the way the module initializes, which includes passing the collection for the current language to drupal (the menu hook I believe) when it initializes the module, and that's the collection that gets used forever after.

Our (slightly time pressed) solution was to just fetch the collections variable every time search was called ignoring the parameter drupal passed it. This definitely works, but it's probably not ideal. A slightly better more general purpose patch (hack) might check if the collections var is multilingual before pulling it, but possibly ideally the module might one day be reworked with multiple collections in mind.

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