Yes, air, more air is being introduced. At idle, it's usually something disconnected or badly sealed like in the vid and thus noticed as there is more vac at idle, but if not seen in the Group 032 LTFT-at idle-block 1(refer to the vid @2:15 to 3:00) then it's likely to be the O2 sensor.
Having the car mapped shouldn't affect it unless very poorly mapped. It's more likely that something was connected poorly...perhaps the intake or anything else recently loosened and re-tightened. Again, it may just be a failed O2. Just doesn't hurt to think on what's recently been handled and recheck those connections as well as all others related to air and vac. Sometimes there's a new leak...something popped off or a new crack in a hose/tube. You can do a smoke test through the intake, but have the ignition on/not running/and have someone open the throttle while inducing with smoke into the intake that you've mostly sealed except for a small tube or hose you can plug after each introduction of smoke.
I tend to replace bits first and if the condition isn't corrected...I swap the bits back and begin searching for alternate causes...leaving me with a spare for later use.