How to reproduce:
1. Open the attached "timeline_animation_window_issue" project
2. Open the "SampleScene"
3. Open the Timeline window (Window > Sequencing > Timeline)
4. Select the "Cube" GameObject in the Hierarchy tab
5. Double-click the "animation" AnimationClip in the Timeline window to open the Animation window (ensure the Animation window was not already open before this step)
6. Attempt to move the Animation window by clicking and dragging the header bar

Expected result: The Animation window is draggable and dockable
Actual result: The Animation window is not draggable until another element within the Animation window is clicked, at which point the Console displays a "Should not be capturing when there is a hotcontrol" warning

Reproducible in: 2021.3.34f1, 2022.3.19f1, 2023.2.8f1, 2023.3.0b4

Reproducible on: Windows 11
Not reproducible on: No other environments tested

Notes:

• The problem does not always seem to reproduce, but closing and reopening the Timeline window should make the issue appear again
• In 2023.2.8f1 and 2023.3.0b4, the window is draggable using the header bar, but not dockable until another element within the Animation window is clicked
• Very rarely reproducible in 2023.3.0b4. Consistently reproducible in 2021.3.34f1 and 2022.3.19f1