Try the Eicar website. Both http and https download should give you the same results.
Aah ofc. the eicar virus test file, didnt think of that, will give it a try.
Just tested and the file was downloaded with SSL, not blocked. After it was download avast removed it to the virus chest after 4-5 secs. I tried downloading the txt file over SSL and it was not removed even after download.
So no SSL scanning and no detecting of the code in the txt after download