One AddOn overriding the other.

[Akryn]

For that particular event, yeah it probably would end up being the order that the addons were loaded, because it fires at login (and when zoning but that doesn't matter) so it's generally registered in top-level code which executes only at load time. So it would be alphabetical, mostly.

What I was saying before though is that an addon can hide or show a frame at arbitrary times, for example in response to the frame being hidden or shown an addon can then re-show/hide it. Or an addon can be programmed so that it waits 2 hours and 11 minutes and then shows the frame. Or anything. So the order that they load or register events for their frame(s) only matters if you already know that they're both calling the Show or Hide method in response to the same thing.

Do you know that both/all addons in question definitely use PLAYER_ENTERING_WORLD and *only* that event?

[Tuhljin]

Originally Posted by Grimsin something has to decide what loads when?

TOC format

See "Dependencies" and "OptionalDeps."