This main window button shows you whether there is an active filter applied on the attribute list panel or not. If there is a filter, the button blinks red and attracts your attention to the fact that you might not see all the attributes that are really there.
In the default configuration, LEX shows all attributes in the attribute
list panel which
are returned from the server. However, you can configure a filter which is applied to the request.
So you could choose for example that only specific attributes are shown in the list - regardless
of what object you examine. Or you could choose to exclude some attributes from the display because
you are connected with low bandwidth to the LDAP server and want to see only what you need.
Please note that the attribute filter works only if there was a correct schema evaluation for the current LDAP server.
To activate and configure a filter for the object list, you can use the Set attribute list filter button or the menu option Tools - Options - Attribute Filter. In this case, the attribute filter dialog is shown:
The filter which is used for the attribute list consists of a list of attributes which can be exclusively included or generally excluded in the attribute list. There are easy ways to save and load filter. LEX stores the appropriate filter files in the Profile and Filter Storage Path in the subdirectory 'LDAPAttributeSets' as text files.
Please remember that the attribute display could also be affected by the configuration for unused attributes. The attribute filter specifies generally what attributes LEX shows in the list, with the Show Only Attributes That Have Values button you configure in addition to that if the empty values are visible or not. So both settings are mixed together.