To keep this error alive you need to create new language keys in your admin panel you copy the string _x_hour_ago and paste in your new key, after that you "translate" to your language and that will be something like that:
_x_hour_ago ---->>> that will be in string or key (i dont remember)
{0} hour{1} ago ---->>> you put that in your language eg. English
and you will do that in every erros that you find like that.