If you change the category of a timeline, it doesn’t get properly attached to the category node. You can see it’s not indented underneath it, and expand/collapse on the category doesn’t show/hide the timeline as expected.
As a side note, it’s very un-discoverable how to even go about adding a timeline. You can’t add them as a component on the components tab. So I would recommend in the list of buttons in the “My Blueprint” tab that has +var, +func, +macro, etc. there should be a +timeline button.
So steps to repro this:
Create a new BP subclassed from HUD
Right click in event graph, pick Add Timeline… from there
Create a dummy variable and give it a category, which it appears under.
Select the timeline and set its category to this new one. It knows it should be in this category, but it is not moved under the category.
Toggle the category open and closed. Actual: The timeline is always visible and not indented under the category. Expected: the timeline acts like the dummy variable
In my example screenshot here, I clicked and dragged the timeline up to the category, but it’s saying you can’t put it into the category it’s already a member of.