@lwc/features

Runtime flags can be enabled or disabled by setting a boolean value for that flag in globalThis.lwcRuntimeFlags, e.g.:

lwcRuntimeFlags.ENABLE_SOME_FEATURE = true;

If the flag is not explicitly set, the feature is disabled by default. The lwcRuntimeFlags object must appear before the engine is initialized and should be defined at the application layer.

Internally, LWC will reference runtime flags like so:

if (lwcRuntimeFlags.ENABLE_SOME_FEATURE) {
    // etc.
}

This makes it possible for consumers to replace these flags at compile time, using something like Rollup's @rollup/plugin-replace or ESBuild's define.

Note that @lwc/features is an internal package used by LWC and (most likely) should not be directly used by consumers.