Added FAQ

FAQ.md

@@ -266,6 +266,7 @@ Fonts, sizes, colors, etc should be material design whenever possible.
 * [(146) How can I fix incorrect message times?](#user-content-faq146)
 * [(147) What should I know about third party versions?](#user-content-faq147)
 * [(148) How can I use an Apple iCloud account?](#user-content-faq148)
+* [(149) How does the unread message count widget work?](#user-content-faq149)
 
 [I have another question.](#user-content-support)
 
@@ -2841,6 +2842,20 @@ When using two-factor authentication you might need to use an [app-specific pass
 
 <br />
 
+<a name="faq149"></a>
+**(149) How does the unread message count widget work?**
+
+The unread message count widget shows the number of unread messages either for all accounts or for a selected account,
+but only for the folders for which new message notifications are enabled.
+
+Tapping on the notification will synchronize all folders for which synchronization is enabled and will open:
+
+* the start screen when all accounts were selected
+* a folder list when a specific account was selected and when new message notifications are enabled for multiple folders
+* a list of messages when a specific account was selected and when new message notifications are enabled for one folder
+
+<br />
+
 ## Support
 
 Only the latest Play store version and latest GitHub release are supported.