How do you get the duration of fights to show up in the chat box after completing things like killing cerb / barrows etc?

I don't think there is one just a tally to know which brothers you've killed so far in the run
/e as far as barrows
/e#2 boss timers plug for runelite

/e#3 think i totally misread this

This post was edited by Exemplary on Jan 24 2022 01:34pm

Runelite may have a plug-in for that. You’d have to check the additional plug in area.

Someone let me know if unofficial clients can’t be discussed and I’ll edit comment.

that's what i'm thinking but i can't seem to find it

As for if it's ok since Runelite is approved by Jagex I believe it's fine