How to merge 
It is possible to merge trips that are consecutive into a single trip.

click the Trips menus

  1. Select the first trip to be merged
  2. Press and hold the "Shift" key
  3. Select the other trips to be merge with the first one (Keep the shift key pressed) 
  4. Right click (While keeping the Shift key pressed) and select "Merge Trips"    

Remember to keep the shift key pressed all the time, after selecting the first trip