Too be honest I haven’t put that much time into the latest development version.
I did notice differences between 3.2.1 and (at the time) current master. I asked about it and some of it is explained with this reply from Aurélien Pierre.
I’m assuming for the moment that there are other tweaks and adjustments done to the algorithms that will show (very?) small differences in the end-result when comparing the same settings in 3.2.1 and 3.3.
I opened the above image in 3.2.1 and, after copying both file and xmp to my 3.3 work area also opened it in the latest master: There’s a very slight difference in luminance, visible in the dark(er) parts. Development version 3.3 being just a tad darker.
I have noticed the new tool-tips in the the development version, which is rather nice, but I haven’t looked at the actual numbers and their meaning just yet.
Anyway, that’s all I can say about your findings. Maybe a developer can shed some more light on that.