Geb cannot see slider that's off the page using an interact block I'm trying to access a menu slider but by the time it would receive the click the slider is off the page. The only work around I have found is to put a Thread.sleep in which I want to avoid using.  Is there another way?

def "Step 5: Can go to the Spanish page"() {
    given:
    at DotComPage                                  

when:                                          
waitFor {usFlagButtonSpanish.displayed}        
interact {                                     
    Thread.sleep(3000)                         
    moveToElement(usFlagButtonSpanish)         
}                                              
usFlagButtonSpanish.click()                    

then:                                          
Thread.sleep(3000)                             
waitFor { MarketLanguageSelectorEsUs }         
Thread.sleep(9000)                             


}
This test is waiting for the usFlagButtonSpanish to be displayed. You can likely resolve your issue by changing 

waitFor {usFlagButtonSpanish.displayed} 


to 

waitFor {usFlagButtonSpanish}