Weird camera bug

[therabug]

Tested versions

4.2.1.stable

System information

Godot v4.2.1.stable - Windows 10.0.22621 - GLES3 (Compatibility) - NVIDIA GeForce GT 1030 (NVIDIA; 31.0.15.4633) - AMD Ryzen 3 1300X Quad-Core Processor (4 Threads)

Issue description

In the 2d viewport when i drag a node that has a camera viewport camera changes to that nodes camera.

2024-01-29.17-29-52.mp4

Steps to reproduce

-Open Godot and create a project
-Create 2 nodes and one of them should have camera 2d node
-Drag node that has camera 2d to other node

Minimal reproduction project (MRP)

N/A

[kleonc]

Reproducible since v4.2.dev4.official [549fcce].
Regression from #79867, cc @WhalesState.

[WhalesState]

Reproducible since v4.2.dev4.official [549fcce]. Regression from #79867, cc @WhalesState.

Tracking the issue, mainly caused by is_editing_in_editor() returns false because it's not part of edited scene is_part_of_edited_scene()

It's caused by the CanvasItemEditor adding preview_node child to the editor viewport, it means Node::is_part_of_edited_scene() returns false, which will not affect the Camera2D only but other nodes with tool scripts that uses this function like Timer and PopupMenu.

preview_issue.mp4