You know, TECHNICALLY this is a “suggestion”, but it’s so obvious I’m reporting it as a bug:
Grim Dawn should have a button on the main menu and/or in the tutorial window that launches the web browser and links to the game guide.
Context: Forums (and reddit) are filled with tons of people asking lots of basic mechanics questions that a simple browsing of the game guide would solve. Most are grateful when referred to the game guide, not having known it was available.