You can make a custom combat chat window without any addon with “what happened to me” and then it’s easy to see what killed you in what order etc without everything else visible. You can look in the tab whenever you want. It will not show percentages though but actual damage.
I personally have several combat windows. One for everything, one for what happened to me, what happened to enemy player and what did enemy npc do etc.
I use Details! for that sometimes. You can look at “damage taken” and if u click your name you will see the damage sources in a list. Then you can also mouse-over to see what spells were used and theres also a tab where you can see what buffs they had and so on.