During the installation, the DBA would have been prompted to carry out the tasks below. If the colours aren't showing, please check the new $OA_HTML directory post upgrade? It may be this step needs to be redone.
2. Adding the Absence Calendar styles (DBA):
IMPORTANT: Do not interupt this patch session. Follow these
instructions in a different session.
1. As the APPLMGR user, login to the Application Tier (APPL_TOP) by
sourcing the environment file.
2. Edit the file Custom.xss or custom.xss, which is located in the
Note: the file will have either a capital 'C' or a lower 'c', depending
on the release.
3. Add the following line to the end of the existing import statements.
For example, if the file already has just one import for oa.xss,
the imports section would look like this:
4. Remove the existing style sheet cache so that the imported styles
5. If this system has multiple Application Tier file systems, repeat
steps 1-4 for each file system.
Without doing this, you won't see colours on the Absence Calendar - you'll just see a letter in each cell.