Some Magento extensions don't play well with Searchanise:
-
SEO Layered Navigation breaks the instant search widget.
Use this workaround*.
-
SEO Suite Ultimate breaks the instant search widget
Use this workaround*.
Lesti::Fpc breaks the instant search widget
Use this workaround*.Extendware Full Page Cache log you out from the Magento admin panel when you go to Catalog → Searchanise.
Disable Primary cache in the Full Page Cache settings to work around this one.
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* Note that Searchanise's full-text search will not work with this workaround.