Ok, I added ports to dash.conf as follows and my progress percentage decreased.
addnode=23.23.186.131
addnode=50.16.206.102
addnode=50.19.116.123
addnode=98.165.130.67
addnode=54.242.50.205
addnode=50.17.98.53
addnode=54.225.43.37
I am trying to sync testnet transactions to my local computer by using Dash Core application. But for some reason, the syncing progress always stuck at 99.83%. I couldn't do anything about it whatever I try. I tried solutions written on "Dash core sync problems" posted by XStreamer at 7 Dec 2017...