If you're using Internet Explorer 7 or 8, these versions are no longer supported by Splunk version 6.1 and higher. You can check out the supporting documentation here regarding supported browsers:
http://docs.splunk.com/Documentation/Splunk/6.1/ReleaseNotes/Deprecatedfeatures#Browser_support
I am using IE 9, and in this sometimes Im getting the timeline while sometimes not so.
Hi @splunkn
What version of Splunk and IE are you using?