Please confirm shortcuts before I add them.
File Menu
=========
New Project - Ctrl/Cmd + N
Open Project - Ctrl/Cmd + O
Close Project - Ctrl/Cmd + W
Save Project - Ctrl/Cmd + S
Save Project As... - <none on linux> should be Ctrl/Cmd + shift + S
Exit Natron - <none> suggest Ctrl/Cmd + Q
Edit Menu
=========
Preferences - <none> suggest Ctrl/Cmd + P
Undo - Ctrl/Cmd + Z
Redo - Ctrl/Cmd + shift + Z
Display Menu
============
New Viewer - Ctrl/Cmd + I
Toggle Full Screen - Meta+Ctrl/^Cmd + F
Options Menu
============
Project Settings - S
Render Menu
===========
Render all writers - F5
Render selected node - F7
Cache Menu
==========
Clear All Memory and Disk Caches - Ctrl/Cmd + shift + K
NodeGraph
=========
Select all nodes - Ctrl/Cmd + A
Select only visible nodes in the visible portion Ctrl/Cmd+shift+A
Frame nodes - F
Display parameters links - shift+e
Expand and focus area - spacebar
Copy - Ctrl/Cmd+C
Cut - Ctrl/Cmd+X
Paste - Ctrl/Cmd+V
Duplicate - Alt+C
Clone - Alt+K
Declone - Alt+shift+K
Switch inputs - shift+X
Add Read node - R
Add Write node - W
Add Roto node - O
Add ColorCorrect node - C
Add Grade node - G
Add Transform node - T
Add Merge node - M
Add node by name - tab
Viewer
======
First frame - Ctrl/Cmd + Left
Play backward - J
Previous frame - Left
Stop - K
Next frame - Right
Play forward - L
Last frame - Ctrl/Cmd + right
Previous keyframe - Ctrl/Cmd + shift + left
Next keyframe - Ctrl/Cmd + shift + right
Previous increment - shift + left
Next increment - shift + right
Scale and center image - F
Clip image to project - shift + C
Display Region of Definition - Shift+C
Display Region of Interest - Shift+W
Proxy mode - Ctrl/cmd P
Refresh previews - P
Expand and focus area - spacebar
Force new render under current frame - U
CurveEditor
===========
Edit
Delete selected keyframes - backspace
Copy selected keyframes - Ctrl/Cmd+C
Paste to selected curve - Ctrl/Cmd+V
Select all keyframes - Ctrl+A
Interpolation
Constant - K
Linear - L
Smooth - Z
Catmull-Rom - R
Cubic - C
Horizontal - H
Break - X
View
Frame seleted curve - F
Roto node
=========
Selection tool - Q
Add tanget points - D
Ellipse/Rectangle/Bezier - V
Tracker node
============
Track backwards - Z
Track previous frame - X
Track next frame - C
Track forward - V
Add new tracker - Ctrl/Cmd+Alt
Ole