Addressing inadvertent changes to the default theme
Pages that ship with the current version use a default theme. The default theme makes it easy to rebrand the portal by assigning a new theme as the default. Administration pages are exceptions and are explicitly assigned the default Portal theme. Doing so ensures that the Administration pages will continue to work correctly if a non-functional theme is inadvertently applied as the default theme.
When you migrate themes to the current version, the default theme assignment from the earlier version is retained and applied to the pages that shipped with the current version.
If you migrate themes from an earlier version and then experience problems with a page that ships with the current version, assign the Portal theme to the page.
If the page works correctly with the Portal theme and not with the migrated theme, there might be functional incompatibilities between the markup in the migrated theme and the content of the portlets.
Portlets on these pages might also be dependent on new function in the current version that did not exist in the earlier version. If so, you might need to copy files from the Portal theme into the migrated theme.
Parent
Post-migration activities