In a piece of code instead of
Thread.sleep (4000);
I want use
from wait.until (ExpectedConditions.visibilityOfElementLocated (By.xpath ("// div [@class = \" x-tool-img x-tool-expand-bottom x-rtl \ "]")));
and i see error but using Thread.sleep I do not have an error message and the code is easily passed i don't no why not pass with wait.until ??
Thank you for your guide