When using a TabbedPage with FormsAppCompatActivity the wrong OnAppearing Method is called.
Clicking on the first tab calls the OnAppearing-Method of the first and the second Page.
Clicking the second page calls the OnAppearing-Method of the third page and so on.
Please see the attached example XF-Project.
Created attachment 17270 [details]
I believe that this particular issue should be fixed by a commit which was merged yesterday to fix #43774 (https://github.com/xamarin/Xamarin.Forms/pull/328) and will be in a future release. If you find it isn't, please feel free to reopen this.
I have checked this issue with Forms version 18.104.22.168-pre2 and observed that this issue has been fixed.
Hence closing this issue.