The behaviour will be described as follows: We edit the article and work paragraph by paragraph. Coming the paragraph x the automatic translator refuses his job and gives only the original version...
On articles that are quite long (those I mentioned earlier: Filippo Coletti, Hanover Square Rooms, but also Conducting), I have sometimes left the interface several times to get to the end and even in case the translation is spread out over weeks and is only repeated occasionally - given the length - this behavior has happened well - oops: the bug works!
For the browser I use Firefox (under Ubuntu LTS 64 bits, so the version follows the majs close enough!) for more than one or two years. I've also used Chromnium in the principal before, but not lately.