As a translator, I want to be able to edit the source article so that I can fix small mistakes in the original article when I detect them during a translation.

For example, the edit
https://en.wikipedia.org/wiki/Adversarial_machine_learning?diff=1008087426
was made while I was translating the article to Portuguese. For such low complexity edits, having the ability to make the fix directly at Special:ContentTranslation, which would take care publishing it to the source wiki, would be very convenient (and reduce the chances of being forgotten if the user do not stop the translation to go fix the article).