Sticky table header not working for Merged cells(rows/columns)

Summary

Sticky table header not working in for Merged cells(rows/columns)

Environment

Browsers : Chrome /Firefox/Safari
Confluence Affected version : 6.5.0

Steps to Reproduce

• Create new page
• Add large table
• Merge either rows/columns
• Try to scroll, header doesn't stick

Expected Results

Table header stick on top of page while scrolling

Actual Results

Header of Table doesn't stick

Workaround

• Sometimes it help clearing plugins cache or reloading confluence