I’m having this same issue. It’s not the most ideal fix, but I’m simply commenting out line 947(ish):
trigger_error( sprintf( '%s is not a valid file or url', $url ), E_USER_WARNING );
Not sure why it doesn’t have some checks to prevent the entire script from dying. Missing the image doesn’t seem to be a kill error.
I’ll check the logic in the whole tbtestimonials_prepare_preloader sometime in the next few days (if I don’t forget, lol) and submit a fix to Travis if I find an easy one.
