How an aircraft (color and icon) and its data tag show up on WebTrak depends on what information was provided to air traffic control and how WebTrak interpreted the info (this explanation is given in the WebTrak documentation).
Also, per the WebTrak documentation, the data is post-processed each night. I’ve been using this for some time and looking at tracks the next day shows some smoothed out, aircraft color and icon changes and in some case, the track disappears completely. I’ve noticed this on some tracks near the fringes of the coverage area, well outside of the DIA noise impact areas.
Compare this track captured today compared to the one MtnBiker2005 posted yesterday. And using it to answer a question posted earlier, note the track southwest of Buckley shows “EAGL1” instead of the 0356 code from yesterday. Eagle 1 is the call sign for the Denver Police helicopter, N710DP.