I’m not going to describe the process of creating a custom master page from end to end, as there are plenty of good articles and blogs out there already. I just want to share one possible pitfall that I fell into…
As any owner of a website might, I decided to create a new master page for my SharePoint Online Public Site. And to save time I started by coping one of the HTML files associated with an “out of the box” mater-pages.
Note: The mso tag contains block SharePoint metadata used by Design Manager to convert the file into a .master file.
After much trial and error I found the “Design Manager” parser seemed to ignores code (or at least mine) that proceeds the mso tags, in the <head /> block. The fix is simple, I added my references just above the mso tags and all will be fine.
If you are interested in what these tag and can be used for, taking a look at this page: http://msdn.microsoft.com/en-us/library/jj822370.aspx
Other useful links:
Update January 2015:
Starting January 2015, Microsoft is making changes to the SharePoint Online Public Website feature. Customers who currently use this feature will continue to have access to the feature for a minimum of two years after the changeover date of March 9, 2015. New customers who subscribe to Office 365 after the changeover date won’t have access to this feature. Moving forward, Office 365 customers will have access to industry-leading third-party offerings that will enable them to have a public website that provides a complete online solution and presence.