triggered?

Literally " but the background was more than serious". To leave this one?

Or the pretext?

I don't get it. You mean all the previous texts?

I agree with the evaluation of the contents of the post but the background (pretext) was more than serious. Is this OK?

I think I'm understanding it now. She agrees with everyone's evaluation (opinion) concerning the contents of Ernst's note, but the back story (?) was more than serious?

Yes. The point was that reason (story) could in some degree excuse/justify the style and content of his note.

right, she justifies it because she thinks it was grounded

https://www.lingvolive.com/ru-ru/translate/ru-en/подоплёка

underlying reason / cause / basis

Oh!

"Agreed in terms of the content of the note". Uly, she agrees with the users' attitude to this post but not with its contents

I understand. That's what this means: I agree (with everyone) in terms of the contents of the note…

I don't think "in terms of the content" fully conveys the meaning as the word "оценка" is missing here ("attitude" in Elena's comment above, "evaluation" in the earlier one - both are not perfect).

assessment?

So, in terms of everyone's assessment of the content of the note?

Ok, I changed it

Yes, now it's good👍

Yes, Uly. I meant that though the note itself is disgusting there is a story behind it that triggered it. All those insulting Dennis' comments which he keeps on with, drove Ernst crazy, I guess. Actually, there was a note before that one, and it was a cry for help as well. But nothing changed since that time. It looks like Dennis developed a taste for bullying his colleagues. Agression without impunity. By no means I meant to justify Ernst's behaviour. (His fault is, clearly, not being strong and or wise enough to withstand the circumstances.) I just wanted everyone to see- do not fight the consequence, fight the reason.

Thank you Tatiana for clearing that up. Now I know that I translated the sentence correctly. Also, your explanation is very well written – almost perfect.

The only mistake: By no means did I mean to justify…

Brava!

Thank you very much, Uly!

Always a pleasure