Problems with autostart after reboot

Hello,
I have problems with the autostart of my MagicMirror. I want that the Mirror starts directly after booting up the RaspberryPi.
Without the autostarting with PM2 the MagicMirror starts after a short time (about 30 seconds). But before the DesktopScreen is displayed (I don’t want to see the desktop). Also if I want to see the processInformation or log with
pm2 show mm
it doesn’t show me anything because mm is not started.
If I say
pm2 start mm.sh
and
pm2 save
a new Instance of Magic Mirror is started.
after a new reboot the RaspberryPi starts again. But I see the desctopScreen and after a short time again the MagicMirror. And now two instances.

I hope you can understand my problem. All I want is that the MagicMirror starts after a reboot without displaying the desctopScreen.

randomnoise

@Johannes I wanted my startup to be as ‘clean’ as possible so I did the following:

Get rid of all the boot text by following https://raspberrypi.stackexchange.com/questions/59310/remove-boot-messages-all-text-in-jessie
Set my desktop background to be completely black (so you don’t see anything before mm starts
Hide the taskbar (only appears back if the mouse is moved to the bottom of the screen).
remove wastebasket from desktop (just right click on it to get option).

By following this now I only see the the ‘acer’ logo which comes from my monitor & can’t be removed, followed by a completely black screen (barring a few small squares as pi boots) then it goes straight in to mm.

Regarding your issue about multiple instances- I think the install script now adds a ‘MagicMirror’ instance to pm2. Then by following the instructions & adding another instance called ‘mm’ I ended up with 2. Think the guide needs to be updated to reflect this. I removed it by using ‘pm2 delete 0’ to remove the 1st instance & then ‘pm2 save’. Hope that is of some help.

Ah, so it was correct that the desctopScreen was displayed first. Now it will also be displayed, but everything is black. I thought the MagicMirror was really startet first.
The problem with the two instances I also found that there was one installed in the MagicMirror folder which always started. I deleted this in pm2 (also the mm.sh file in the MagicMirror folder) and add the new one in Home-folder.

Thank you a lot