Support React 16 of webapp for loading icon
Support React 16 of webapp for loading icon

data-reactroot is no longer used in React 16
https://stackoverflow.com/questions/47203183/missing-data-reactroot-attirbute-in-react-16

yuya-oc/desktop,yuya-oc/desktop,yuya-oc/electron-mattermost,mattermost/desktop,mattermost/desktop,mattermost/desktop,yuya-oc/desktop,mattermost/desktop,mattermost/desktop,yuya-oc/electron-mattermost,yuya-oc/electron-mattermost