I'm currently using X-notifier for 3 accounts: A Gmail account, a Yahoo account and an Outlook account. If I enabled the "Continue running background apps when Google Chrome is closed" Chrome setting, and close Chrome for a while, and then (after 10-20 minutes) reopen it, Outlook and Yahoo accounts keep in a condition of continue searching for mails without success and blocks X-notifier which shows a small squared red icon instead of the # of mails
If I uncheck the "Continue running background apps when Google Chrome is closed" option, X-notifier resumes working normally.