src/vs/base/common/mime.ts/clearTextMimes
export function clearTextMimes(onlyUserConfigured?: boolean): void {
	if (!onlyUserConfigured) {
		registeredAssociations = [];
		nonUserRegisteredAssociations = [];
		userRegisteredAssociations = [];
	} else {
		registeredAssociations = registeredAssociations.filter(a => !a.userConfigured);
		userRegisteredAssociations = [];
	}
}