Event Timeline Correctness Checking Reports
On the Event Timeline chart correctness checking reports (CCRs) are displayed as
yellow-bordered circles. The color of each circle depends on the type of the
particular report: if it is an error then the color is black, if it is a warning -
the color is grey.
Event Timeline with CCRs of Both Types:

You can turn on/off the display of CCRs through the context menu: right-click the
chart, go to the
Show
submenu and check/uncheck the Issues
item. The
display is turned on by default.