Many will be out of date the day the patch drops but otherwise still work as long as you check the "Allow out of date AddOns" checkbox on your character select screen.
Usually, AddOns that are actively supported will be updated within the first few days after a bigger patch to match the new API version number and/or fix any problems related to API updates.
The checkbox was removed at it was nonsense. You get a notification now as you login if your addons contain outdated ones, once after a patch.
Just wait a few days, most addons get updated quickly/are already updated and the update just needs some time to register them all at www.esoui.vom and thus at Minion.
If you get any error messages report them at the addons websites comments and tell the dev how to get to the error in detail. That will help to fix it. And please always test without any other addon enabled if you get error messages to make sure it's the addon itself and not any other addon interfering!
What do you mean "nonsense"? I have a few addons that are years out-of-date, not maintained, and yet have worked just fine when I ticked the erstwhile box. As I really am not comfortable playing the game without those addons, I'm glad that my subscription just ran out so I don't have to worry about it when I just log on daily for the (measly) reward. Meanwhile, I'm hoping that the checkbox will be returned so I can resume playing; frankly, the sooner the better.
What do you mean "nonsense"? I have a few addons that are years out-of-date, not maintained, and yet have worked just fine when I ticked the erstwhile box. As I really am not comfortable playing the game without those addons, I'm glad that my subscription just ran out so I don't have to worry about it when I just log on daily for the (measly) reward. Meanwhile, I'm hoping that the checkbox will be returned so I can resume playing; frankly, the sooner the better.
Woops, looks like I misunderstood how it works and out-of-date addons are in fact enabled unless I untick them myself. Please ignore my outraged diatribe while I go hide my head in shame.