Which addons are obsolete tomorrow?

[Polarthief]

I don't typically follow much about an expansion outside of major features like new systems (Transmog/Artifact), class changes, and the general stuff here and there, but I don't know much about which of my addons become obsolete (e.g., when QuestHelper became useless when Blizzard implemented their own version). Does someone happen to know what all the new systems are that makes some addons obsolete so I can clean out my interface in preparation for tomorrow?

[purebalance]

Define obsolete? Like not needed? Or just won't work?

Off topic: I love patch days when the little add on addicted idiots run around like a chicken with their head chopped off or that it's the end of the world. I loved loved whatever that one add on that was broken for like 2 weeks in 6.2

[Infracted]

[ComputerNerd]

Nothing immediately springs to mind.
Even MasterPlan continues to have some functionality going forward, and there may be reasons for some players to still use their garrisons.
Professions in particular.

[Syld]

Probably most of them will stop working tomorrow

[Jellospally]

Probably most of them will stop working tomorrow

Most addon creators have their addons working on PTR/Beta which is technically what we have tomorrow so those versions will work on it.

[Cinnamohn]

Besides MasterPlan, I don't think any of them. Maybe Tidyplates, if you prefer their version of nameplates.

[Andyo]

Helm n Cloak, such a great little addon, will be no more.

[ComputerNerd]

Helm n Cloak, such a great little addon, will be no more.

Good example.
Actually obselete