Custom master page breaks “Change the look”

Question

• In Design Manager: Edit Master Pages click on "Create a minimal master page" and ensure the new master page is published:

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• In Site Master Page Settings set this new master page as the default for pages and system pages:

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• In Change the look choose any of the default looks e.g. Orange:

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• The subsequent designbuilder.aspx page hangs with no preview (with the message "Working on it..." in the top-right):

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• Click Try it out presents a correlation ID error:

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Can someone help with the missing step?

Answer 1

The Theme wasn't properly configured.

In particular, the fact that the ".preview" file was not properly configured was the reason that the designbuilder.aspx page was breaking.

The below Microsoft articles need to read to understand how all the relevant theme files interact:

• Themes Overview
• How To Create A Master Page Preview File In SharePoint
• How To Deploy A Custom Theme In SharePoint
• How To Make Custom CSS Files Themable In SharePoint
• Upgrade Custom Themes And CSS To SharePoint
• Color Palettes And Fonts In SharePoint

The below components need to be considered for a successful theme: - Color Palette - Font Scheme - Master Page - Master Page Preview - Composed Look - Change the Look - Design Gallery