Cargo Features

[dependencies]
relm4-macros = { version = "0.8.1", default-features = false, features = ["relm4"] }
default = relm4

The relm4 feature is set by default whenever relm4-macros is added without default-features = false somewhere in the dependency tree.

relm4 default

Without the default "relm4" feature, all imports of gtk will be use gtk; instead of use relm4::gtk; thus making it easier to use this crate without Relm4.