Export a set of 480 RAW files with various develop edits, to 8-bit TIF
The progress bar in the Lightroom modules panel/bar and and Windows taskbar button should show accurate ratio and percentage of completion while the export job is running.
When the Lightroom modules panel/bar is minimized, the progress bar only moves up to 7% of the length until the entire job is completed. If the modules panel/bar is maximized, the progress bar shows an accurate proportion.
The Windows taskbar button displays from 0% to 3% when 30% of the job is complete, and up to 7% when 60% of the job is complete. It never goes over 7% even when the job nears 100% completion. The green progress bar in the taskbar button reflects the same erroneous progress value.