I am working on a new Office 365 SharePoint 2013 online site collection. now when i investigate the admin options i found that these 2 options are disabled inside my Office 365:-
1- "Custom Script"
2- "Enable Customizing Master Pages and Page Layouts"
now i need to enable both options. first option to be able to add script editor web parts to my pages , second option to be able to customize page layouts.
but before enabling these 2 options inside my Office 365, can anyone advice why these options are disabled by default inside SharePoint online (office 365) while they are enabled by default inside SharePoint 2013 on-premise ? i mean are there any security problems or other limitations i need to be aware of before enabling these 2 options ?