1. Find a site with a call stack long enough that it will be taller than the call stack window. 2. In the sources tab, Set the breakpoint, reload the page 3. Position the cursor on the top of the call stack 4. The stack is highlighted in blue. 5. Hit the arrow down key and maintain 6. The blue highlight is going down, the call stack is scrolling. 7. Now once the bottom is reached, hit the arrow up key and maintain. Expected: The blue highlight until we reach the top Actual: As soon as we reach the top of the viewing area of the call stack, the highlight disappear. The scroll is happening but no more blue.