One of these is a bug I reported for 2.22 but was never fixed.
1. When viewing a chart, you lose the ability to "pinpoint" a set of data. You can't click anywhere in the chart to get the vertical line to show up. Sometimes I can get around this by playing my log back and pausing it.
2. When you modify the chart settings and try to type a value for the range, you cannot enter a clean new number by starting with nothing. You have to have a value in the box first and then have to use the cursor to go ahead of that initial number to input what you want.