Didn’t have to wait till next week - I found a few old projects on the hard drive. For these experiments, I didn’t launch Audacity and then browse for the project, I just dragged the .aup file to Audacity to launch & load. I tried 2.0.3, 2.1.1, and 2.1.2, but it appeared the “slow history” issue is common to 2.1.1 and 2.1.2 so I started comparing 2.1.1 with 2.0.3.
Project 2016.01.13PM (possibility of having opened this project previously, it was on the HD but I hadn’t started working on it):
Launch/load 2.1.1 4 sec
History 18 sec 1.0 GB
Close immediate
Launch/Load 2.1.2 5 sec
History 1 sec 1.0 GB
Close immediate
==============================
Project 2010.10.17PM (from HD):
Launch/Load 2.1.1: 4 sec
History 23 sec 1.7 GB
Close immediate
Launch/Load 2.1.2: 3 sec
History 1 sec 1.7 GB
Close immediate
==============================
Project 2010.11.14AM (from HD):
Launch/Load 2.0.3: 35 sec after subtracting time that error dialog (ffmpeg config) was displayed.
History immediate 1.9 GB
Close immediate
Load/Launch 2.1.1 3 sec
History 1 sec 1.9 GB
Close immediate
=============================
Project 2011.02.27AM (from HD, had opened project on 4/4/2015, the date from export files):
Load/Launch 2.1.1: 3 sec
History 24 sec 1.6 GB
Close immediate
Load/Launch 2.0.3: 3 sec after subtracting time error dialog (ffmpeg config) was displayed
History immediate 1.6 GB
Close immediate
Load/Launch 2.1.1 3 sec
History 1 sec 1.6GB
Close immediate
So History display after loading the project on 2.0.3 is pretty quick regardless of whether any of these Audacity versions has displayed it previously. It’s very slow on 2.1.1 and 2.1.2 unless it has been displayed previously by some version of Audacity.