We are sorry for the inconvenience caused. I understand that widget keeps disappearing in your mobile device. Please check if the Android is up-to-date, if there is any update available for the device in your settings, check the software update and update your mobile, after updating try uninstall and reinstalling the McAfee application one more time and allow all the permission in the application. Kindly turn on McAfee security by following the steps
For example: Go to settings >> accessibility >> McAfee security>> enable.
Go to settings >> application >> McAfee >> permission >> enable all the permission
Finally if all the features are enabled and if the issue still persist. Please let us know.