List of poorly documented features and tricks

**Your Godot version:**
4.0

**Issue description:**
Here's the list of stuff I mentioned in https://github.com/godotengine/godot-docs/issues/3969#issuecomment-687590890
I'm not sure actually how much of this is documented, but I bet not all of it. Also the list isn't exhaustive. If you know something that isn't here and isn't well known, comment and I will add it.

**Things that are not documented nor indicated anywhere**
- You can hold Shift when dragging a node in Scene Tree Dock to keep local transform
- If you hold Ctrl while dragging a script file onto a node in scene tree, it will be instantiated as a new node instead of attached
- You can drag and drop nodes (1 or more) from Scene Tree into Script Editor to insert their path
- holding Ctrl will insert `@onready` variable
- You can drag and drop files (1 or more) from FileSystem Dock into Script Editor to insert their path
- holding Ctrl will make the file(s) preloaded
- Shift + Clicking the folding arrow in Scene Tree will fold/unfold recursively
- Same as above, but with files from FileSystem Dock
- You can drag and drop a resource from the inspector (e.g. material) to FileSystem to save it as file
- You can hold Ctrl while dragging a 2D node to quick-enable smart snapping
- You can hold Shift while dragging a 2D node to snap it to an axis
- You can drop a project file/directory into Project Manager to add it to project list
- You can press Backspace while drawing a 2D polygon to undo last point or press Enter to close the polygon
- When you hold Ctrl when moving a file in FileSystem, it will be copied instead of moved
- You can drop a file from outside onto Godot editor to copy it to the currently selected directory in FileSystem
- You can hold Ctrl when dropping texture to SpriteFrames to load it as spritesheet
- When you hold Alt while dragging timeline in Animation, the animation won't update (only time changes)
- When you hold Alt while changing RectangleShape2D, it will change symmetrically
- When you hold Shift when pressing arrows to move 2D node, the movement will be snapped to grid
- When you drag and drop node branch from Scene Tree to Filesystem, it will be saved as scene
- If you hold Shift while clicking animation timeline, your step will be divided by 4
- Alt + Mouse Wheel on animation track will move timeline cursor step by step
- Add Shift to move by 1/4 step
- when you add a meta `_editor_icon` to any node, the icon will be used in the editor (might get deprecated in 4.0)
- Right-click on SpinBox arrow will instantly set the value to min/max
- Renaming a node to an empty name automatically makes it have its base class' name

**Things that are handy, but not documented and easy to miss**
- If you disable `Editor Settings/Editors/2D/Constrain Editor View`, you can move freely in 2D editor
- When you double click an audio resource, an audio player will appear at the bottom of the inspector. It's especially useful to easily preview custom loop points in audio files
- Assigning a ButtonGroup to a CheckBox will change it visually to radio button
- `Editor Settings/Interface/Scene Tabs/Restore Scenes On Load` can be enabled to automatically open last opened scenes
- If you have 2 monitors, you can change `Editor Settings/Run/Window Placement/Screen` to run the project on another monitor from the editor
- In Misc tab in the debugger you can see what Control node was just clicked
- You can use `Project Settings/Editor/Search In File Extensions` to add more files for searching with Search In Files (e.g. you can add .tscn to search in scenes)
- If you need to quickly go to project user data directory, use Project -> Open Project Data Folder
- You can evaluate expression inside Script Editor by using Edit -> Evaluate Expression. E.g. you can write `1 + 2`, select it and press Ctrl + Shift + E to turn it into `3`
- When you have an empty scene, instead of picking root node you can press the star icon to select from favorite nodes
- 2D Select Tool has lots of useful functionality, which is only mentioned in a long tooltip

**Misc tricks**
- If you want to delete nodes without confirmation, you can unbind the default 'Delete Node' shortcut and bind 'Delete (no confirm)' instead
- If you have a node at (0, 0) and want to very quickly move it to the position of another node, you can reparent it to that node while holding Shift and then reparent back with Shift released
- You can hide scrollbars of TextEdit if you set their modulate to 0 and mouse filter to ignore
- You can get a global reference to SceneTree (even from outside tree) by using `Engine.get_main_loop()`
- If some method requires method name (e.g. `SceneTree.call_group()`), you can avoid using strings by using `some_func.get_method()`, which returns Callable's name

Maybe I should turn these into checkboxes to make a tracker?