WowAce

Currently, there is no addon support for the MoP Classic release. The Cata addon does not work with the new update even when manually dropping the file into the MoP folder

In particular, decursive does not see magic debuffs on other players, only on himself. maybe this is due to the new passive talent

I've just released an alpha version (https://www.wowace.com/projects/decursive/files) for very basic compatibility with MoP, but without any spell updates.

If possible, post your class and the spell name/spell id that are not working properly in the current alpha version and what you know about the spell mechanic (related talents), this will speed up the fixes.

As Hpal magic debuffs on other players are still not visible. Despite this, poisons and diseases are visible.

Cleanse, https://www.wowhead.com/mop-classic/spell=4987/cleanse

I repeat that this may be due to the passive talent that has hpal for dispelling magical debuffs.
Sacred Cleansing, https://www.wowhead.com/mop-classic/spell=53551/sacred-cleansing