Pseudo-debuff timer addons not working in classic?

I’m aware the actual debuff timers aren’t a thing, but I remember distinctly back in the day that several addons would give you debuff timers that are client side and based on when you cast the spell and how long its supposed to last.

I’m trying, for example, to use this wago weakaura on my warlock: /plnU7EMi1

But no actual timer displays when I cast my DOTs, its just blank. This happens for all timer addons I’ve tried, is there some setting I have to change?

https://www.curseforge.com/wow/addons/omni-cc

or are you thinking more
https://www.wowinterface.com/downloads/info7532-ForteXorcist.html

I solved my issue, all of the addons I’ve tried actually do work, it was ElvUI that was breaking the timers.