If any tabs are undocked from the main viewport and another tab is then docked to the main viewport it will hide any undocked tabs. This only appears to affect tabs that in the Menu > Window with exception of Project and Editor settings.

See attached image gif for demonstration

Steps to Reproduce

1.Open UE4
2. Undock any of the four main tabs (Details, Modes, Outliner, Content Browser)
3. Open a static mesh or blueprint
4. doc the opened tab to the main viewport if it doesn't do so automatically
5. undocked tab disappears

Have Comments or More Details?

Head over to the existingAnswerHub thread and let us know what's up.

Login to Vote

By Design
ComponentTools - Slate
Affects Versions4.
CreatedMar 3, 2015
ResolvedMar 3, 2015
UpdatedApr 27, 2018