The only annoying thing Android Marshmallow users may come across is the selection of MTP mode each time they connect their phone to their PC.  This is a process that should be by default selecting the MTP without the user having to choose manually each time.  XDA senior member bitstra came up with a solution.

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Bitstra’s application “MTP Enabler” automatically changes the USB mode to MTP when you connect your phone to your PC.  Bistra’s app allows you to place a widget on your phone desktop screen.  You can simply tap the widget to activate the MTP enabler application and background will be changed to orange. MTP enabler can also listen to the broadcast intent generated by USB connection but this is still in experimental mode, so gofor the widget option as it is more stable.

MTP enabler doesn’t modify any system files on your Android OS. It won’t harm your device’s security or privacy in anyway.

By default your connection type is set to “MTP” mode in the MTP Enabler application, but you can also change this option to “Ask me before”.

Upon enabling “Ask me before” option, it will ask you what type of connect you want to go with upon connecting your phone with your PC.

The beautiful thing about MTP enabler is that it won’t drain your battery.  What are you waiting for? go and grab the MTP enable application and install it on your Android Marshmallow phone right away.

How To Fix Android Marshmallow MTP Issue

Make sure that your phone is rooted (busy box isn’t necessary) and is running Android Marshmallow.

This application works with almost all Android Marshmallow ROMs (Samsung, LG, Moto, Sony Xperia, HTC and more).
Download & install MTP Enabler application.
Add the MTP Enabler widget to your phone’s homescreen to access it easily.
You can also setup MTP Enabler by accessing it through app drawer.

For more info follow