Cargo Features

[dependencies]
imgui-gfx-renderer = { version = "0.8.2", default-features = false, features = ["opengl", "directx"] }
default = opengl

The opengl feature is set by default whenever imgui-gfx-renderer is added without default-features = false somewhere in the dependency tree.

opengl default
directx

imgui-gfx-renderer has 3 features without comments.